diff --git a/config/config.toml b/config/config.toml
index 21385f5d0..3e75d284e 100644
--- a/config/config.toml
+++ b/config/config.toml
@@ -16,6 +16,7 @@ filesystem_cache_type=""
 resolve_result_entry=0
 debug=false
 allow_no_verification=true
+allow_idmap=true
 # disable_verification=false
 # Causes TestRunWithDefaultConfig to break, but
 # fine to use in /etc/soci-snapshotter-grpc-config.toml
diff --git a/config/fs.go b/config/fs.go
index 4088d9b6e..05e5978e7 100644
--- a/config/fs.go
+++ b/config/fs.go
@@ -56,6 +56,7 @@ type FSConfig struct {
 	NoPrometheus                   bool   `toml:"no_prometheus"`
 	MountTimeoutSec                int64  `toml:"mount_timeout_sec"`
 	FuseMetricsEmitWaitDurationSec int64  `toml:"fuse_metrics_emit_wait_duration_sec"`
+	AllowIdMap                     bool   `toml:"allow_idmap" default:"true"`
 
 	RetryableHTTPClientConfig `toml:"http"`
 	BlobConfig                `toml:"blob"`
diff --git a/fs/fs.go b/fs/fs.go
index 40011bf8e..10072baef 100644
--- a/fs/fs.go
+++ b/fs/fs.go
@@ -47,7 +47,9 @@ import (
 	"fmt"
 	golog "log"
 	"net/http"
+	"os"
 	"os/exec"
+	"path/filepath"
 	"sync"
 	"syscall"
 	"time"
@@ -59,6 +61,7 @@ import (
 	layermetrics "github.com/awslabs/soci-snapshotter/fs/metrics/layer"
 	"github.com/awslabs/soci-snapshotter/fs/remote"
 	"github.com/awslabs/soci-snapshotter/fs/source"
+	"github.com/awslabs/soci-snapshotter/idtools"
 	"github.com/awslabs/soci-snapshotter/metadata"
 	"github.com/awslabs/soci-snapshotter/snapshot"
 	"github.com/awslabs/soci-snapshotter/soci"
@@ -67,6 +70,7 @@ import (
 	ctdsnapshotters "github.com/containerd/containerd/pkg/snapshotters"
 	"github.com/containerd/containerd/reference"
 	"github.com/containerd/containerd/remotes/docker"
+	"github.com/containerd/errdefs"
 	"github.com/containerd/log"
 	metrics "github.com/docker/go-metrics"
 	fusefs "github.com/hanwen/go-fuse/v2/fs"
@@ -455,6 +459,79 @@ func (fs *filesystem) getSociContext(ctx context.Context, imageRef, indexDigest,
 	return c, err
 }
 
+func (fs *filesystem) getIdMappedMountpoint(mountpoint, activeLayerKey string) string {
+	d := filepath.Dir(mountpoint)
+	return filepath.Join(fmt.Sprintf("%s_%s", d, activeLayerKey), "fs")
+}
+
+func (fs *filesystem) IdMapMount(ctx context.Context, mountpoint, activeLayerKey string, idmapper idtools.IDMap) (string, error) {
+	newMountpoint := fs.getIdMappedMountpoint(mountpoint, activeLayerKey)
+	log.G(ctx).WithField("mountpoint", newMountpoint).Info("creating remote id-mapped mount")
+	if err := os.Mkdir(filepath.Dir(newMountpoint), 0700); err != nil {
+		return "", err
+	}
+	if err := os.Mkdir(newMountpoint, 0755); err != nil {
+		return "", err
+	}
+
+	fs.layerMu.Lock()
+	l := fs.layer[mountpoint]
+	if l == nil {
+		fs.layerMu.Unlock()
+		log.G(ctx).WithField("mountpoint", newMountpoint).Info("failed to create remote id-mapped mount")
+		return "", errdefs.ErrNotFound
+	}
+	fs.layer[newMountpoint] = l
+	fs.layerMu.Unlock()
+	node, err := l.RootNode(0, idmapper)
+	if err != nil {
+		return "", err
+	}
+
+	rawFS := fusefs.NewNodeFS(node, &fusefs.Options{
+		AttrTimeout:     &fs.attrTimeout,
+		EntryTimeout:    &fs.entryTimeout,
+		NegativeTimeout: &fs.negativeTimeout,
+		NullPermissions: true,
+	})
+	mountOpts := &fuse.MountOptions{
+		AllowOther:    true,   // allow users other than root&mounter to access fs
+		FsName:        "soci", // name this filesystem as "soci"
+		Debug:         fs.debug,
+		DisableXAttrs: l.DisableXAttrs(),
+		Options:       []string{"default_permissions", "ro"},
+	}
+	if _, err := exec.LookPath(fusermountBin); err == nil {
+		mountOpts.Options = []string{"suid"} // option for fusermount; allow setuid inside container
+	} else {
+		log.G(ctx).WithError(err).Infof("%s not installed; trying direct mount", fusermountBin)
+		mountOpts.DirectMount = true
+	}
+	server, err := fuse.NewServer(rawFS, newMountpoint, mountOpts)
+	if err != nil {
+		log.G(ctx).WithError(err).Debug("failed to make filesystem server")
+		return "", err
+	}
+
+	go server.Serve()
+
+	log.G(ctx).WithField("mountpoint", newMountpoint).Info("successfully created remote mountpoint")
+	return newMountpoint, server.WaitMount()
+}
+
+func (fs *filesystem) IdMapMountLocal(ctx context.Context, mountpoint, activeLayerKey string, idmapper idtools.IDMap) (string, error) {
+	newMountpoint := fs.getIdMappedMountpoint(mountpoint, activeLayerKey)
+	log.G(ctx).WithField("mountpoint", newMountpoint).Info("creating local id-mapped mount")
+
+	if err := idtools.RemapDir(ctx, mountpoint, newMountpoint, idmapper); err != nil {
+		log.G(ctx).WithField("mountpoint", newMountpoint).Errorf("failed to create local mount: %v", err)
+		return "", err
+	}
+
+	log.G(ctx).WithField("mountpoint", newMountpoint).Info("successfully created local mountpoint")
+	return newMountpoint, nil
+}
+
 func (fs *filesystem) Mount(ctx context.Context, mountpoint string, labels map[string]string) (retErr error) {
 	// Setting the start time to measure the Mount operation duration.
 	start := time.Now()
@@ -566,7 +643,7 @@ func (fs *filesystem) Mount(ctx context.Context, mountpoint string, labels map[s
 	// Maybe we should reword the log here or remove it entirely,
 	// since the old Verify() function no longer serves any purpose.
 
-	node, err := l.RootNode(0)
+	node, err := l.RootNode(0, idtools.IDMap{})
 	if err != nil {
 		log.G(ctx).WithError(err).Warnf("Failed to get root node")
 		retErr = fmt.Errorf("failed to get root node: %w", err)
@@ -602,6 +679,7 @@ func (fs *filesystem) Mount(ctx context.Context, mountpoint string, labels map[s
 		Debug:         fs.debug,
 		Logger:        golog.New(logger, "", 0),
 		DisableXAttrs: l.DisableXAttrs(),
+		Options:       []string{"default_permissions", "ro"},
 	}
 	if _, err := exec.LookPath(fusermountBin); err == nil {
 		mountOpts.Options = []string{"suid"} // option for fusermount; allow setuid inside container
@@ -692,7 +770,8 @@ func (fs *filesystem) Unmount(ctx context.Context, mountpoint string) error {
 	l, ok := fs.layer[mountpoint]
 	if !ok {
 		fs.layerMu.Unlock()
-		return fmt.Errorf("specified path %q isn't a mountpoint", mountpoint)
+		log.G(ctx).Errorf("specified path %q isn't a remote mount", mountpoint)
+		return errdefs.ErrNotFound
 	}
 	delete(fs.layer, mountpoint) // unregisters the corresponding layer
 	l.Done()
@@ -706,6 +785,10 @@ func (fs *filesystem) Unmount(ctx context.Context, mountpoint string) error {
 	return syscall.Unmount(mountpoint, syscall.MNT_FORCE)
 }
 
+func (fs *filesystem) UnmountLocal(ctx context.Context, mountpoint string) error {
+	return syscall.Unmount(mountpoint, syscall.MNT_FORCE)
+}
+
 // neighboringLayers returns layer descriptors except the `target` layer in the specified manifest.
 func neighboringLayers(manifest ocispec.Manifest, target ocispec.Descriptor) (descs []ocispec.Descriptor) {
 	for _, desc := range manifest.Layers {
diff --git a/fs/fs_test.go b/fs/fs_test.go
index 2591a270a..119ec9c2c 100644
--- a/fs/fs_test.go
+++ b/fs/fs_test.go
@@ -46,6 +46,7 @@ import (
 	"github.com/awslabs/soci-snapshotter/fs/layer"
 	"github.com/awslabs/soci-snapshotter/fs/remote"
 	"github.com/awslabs/soci-snapshotter/fs/source"
+	"github.com/awslabs/soci-snapshotter/idtools"
 	"github.com/containerd/containerd/reference"
 	"github.com/containerd/containerd/remotes/docker"
 	fusefs "github.com/hanwen/go-fuse/v2/fs"
@@ -83,10 +84,12 @@ func (l *breakableLayer) Info() layer.Info {
 		Size: 1,
 	}
 }
-func (l *breakableLayer) DisableXAttrs() bool                           { return false }
-func (l *breakableLayer) RootNode(uint32) (fusefs.InodeEmbedder, error) { return nil, nil }
-func (l *breakableLayer) Verify(tocDigest digest.Digest) error          { return nil }
-func (l *breakableLayer) SkipVerify()                                   {}
+func (l *breakableLayer) DisableXAttrs() bool { return false }
+func (l *breakableLayer) RootNode(uint32, idtools.IDMap) (fusefs.InodeEmbedder, error) {
+	return nil, nil
+}
+func (l *breakableLayer) Verify(tocDigest digest.Digest) error { return nil }
+func (l *breakableLayer) SkipVerify()                          {}
 func (l *breakableLayer) ReadAt([]byte, int64, ...remote.Option) (int, error) {
 	return 0, fmt.Errorf("fail")
 }
diff --git a/fs/layer/layer.go b/fs/layer/layer.go
index 91479ea84..778278bf7 100644
--- a/fs/layer/layer.go
+++ b/fs/layer/layer.go
@@ -58,6 +58,7 @@ import (
 	"github.com/awslabs/soci-snapshotter/fs/remote"
 
 	spanmanager "github.com/awslabs/soci-snapshotter/fs/span-manager"
+	"github.com/awslabs/soci-snapshotter/idtools"
 	"github.com/awslabs/soci-snapshotter/metadata"
 	"github.com/awslabs/soci-snapshotter/soci"
 	"github.com/awslabs/soci-snapshotter/util/lrucache"
@@ -86,7 +87,7 @@ type Layer interface {
 	Info() Info
 
 	// RootNode returns the root node of this layer.
-	RootNode(baseInode uint32) (fusefs.InodeEmbedder, error)
+	RootNode(baseInode uint32, idMapper idtools.IDMap) (fusefs.InodeEmbedder, error)
 
 	// Check checks if the layer is still connectable.
 	Check() error
@@ -489,14 +490,14 @@ func (l *layerRef) Done() {
 	l.done()
 }
 
-func (l *layer) RootNode(baseInode uint32) (fusefs.InodeEmbedder, error) {
+func (l *layer) RootNode(baseInode uint32, idMapper idtools.IDMap) (fusefs.InodeEmbedder, error) {
 	if l.isClosed() {
 		return nil, fmt.Errorf("layer is already closed")
 	}
 	if l.r == nil {
 		return nil, fmt.Errorf("layer hasn't been verified yet")
 	}
-	return newNode(l.desc.Digest, l.r, l.blob, baseInode, l.resolver.overlayOpaqueType, l.resolver.config.LogFuseOperations, l.fuseOperationCounter)
+	return newNode(l.desc.Digest, l.r, l.blob, baseInode, l.resolver.overlayOpaqueType, l.resolver.config.LogFuseOperations, l.fuseOperationCounter, idMapper)
 }
 
 func (l *layer) ReadAt(p []byte, offset int64, opts ...remote.Option) (int, error) {
diff --git a/fs/layer/node.go b/fs/layer/node.go
index 6459c1a48..bbb813f79 100644
--- a/fs/layer/node.go
+++ b/fs/layer/node.go
@@ -56,6 +56,7 @@ import (
 	commonmetrics "github.com/awslabs/soci-snapshotter/fs/metrics/common"
 	"github.com/awslabs/soci-snapshotter/fs/reader"
 	"github.com/awslabs/soci-snapshotter/fs/remote"
+	"github.com/awslabs/soci-snapshotter/idtools"
 	"github.com/awslabs/soci-snapshotter/metadata"
 	"github.com/containerd/log"
 	fusefs "github.com/hanwen/go-fuse/v2/fs"
@@ -189,7 +190,7 @@ func (f *FuseOperationCounter) Run(ctx context.Context) {
 
 // logFSOperations may cause sensitive information to be emitted to logs
 // e.g. filenames and paths within an image
-func newNode(layerDgst digest.Digest, r reader.Reader, blob remote.Blob, baseInode uint32, opaque OverlayOpaqueType, logFSOperations bool, opCounter *FuseOperationCounter) (fusefs.InodeEmbedder, error) {
+func newNode(layerDgst digest.Digest, r reader.Reader, blob remote.Blob, baseInode uint32, opaque OverlayOpaqueType, logFSOperations bool, opCounter *FuseOperationCounter, idMapper idtools.IDMap) (fusefs.InodeEmbedder, error) {
 	rootID := r.Metadata().RootID()
 	rootAttr, err := r.Metadata().GetAttr(rootID)
 	if err != nil {
@@ -210,9 +211,10 @@ func newNode(layerDgst digest.Digest, r reader.Reader, blob remote.Blob, baseIno
 	}
 	ffs.s = ffs.newState(layerDgst, blob)
 	return &node{
-		id:   rootID,
-		attr: rootAttr,
-		fs:   ffs,
+		id:       rootID,
+		attr:     rootAttr,
+		fs:       ffs,
+		idMapper: idMapper,
 	}, nil
 }
 
@@ -272,9 +274,10 @@ func (fs *fs) inodeOfID(id uint32) (uint64, error) {
 // node is a filesystem inode abstraction.
 type node struct {
 	fusefs.Inode
-	fs   *fs
-	id   uint32
-	attr metadata.Attr
+	fs       *fs
+	id       uint32
+	attr     metadata.Attr
+	idMapper idtools.IDMap
 
 	ents       []fuse.DirEntry
 	entsCached bool
@@ -407,14 +410,14 @@ func (n *node) Lookup(ctx context.Context, name string, out *fuse.EntryOut) (*fu
 				n.fs.reportFailure(fuseOpLookup, fmt.Errorf("%s: %v", fuseOpLookup, err))
 				return nil, syscall.EIO
 			}
-			entryToAttr(ino, tn.attr, &out.Attr)
+			n.entryToAttr(ino, tn.attr, &out.Attr)
 		case *whiteout:
 			ino, err := n.fs.inodeOfID(tn.id)
 			if err != nil {
 				n.fs.reportFailure(fuseOpLookup, fmt.Errorf("%s: %v", fuseOpLookup, err))
 				return nil, syscall.EIO
 			}
-			entryToAttr(ino, tn.attr, &out.Attr)
+			n.entryToAttr(ino, tn.attr, &out.Attr)
 		default:
 			n.fs.reportFailure(fuseOpLookup, fmt.Errorf("%s: unknown node type detected", fuseOpLookup))
 			return nil, syscall.EIO
@@ -463,10 +466,11 @@ func (n *node) Lookup(ctx context.Context, name string, out *fuse.EntryOut) (*fu
 		return nil, syscall.EIO
 	}
 	return n.NewInode(ctx, &node{
-		id:   id,
-		fs:   n.fs,
-		attr: ce,
-	}, entryToAttr(ino, ce, &out.Attr)), 0
+		id:       id,
+		fs:       n.fs,
+		attr:     ce,
+		idMapper: n.idMapper,
+	}, n.entryToAttr(ino, ce, &out.Attr)), 0
 }
 
 var _ = (fusefs.NodeOpener)((*node)(nil))
@@ -495,7 +499,7 @@ func (n *node) Getattr(ctx context.Context, f fusefs.FileHandle, out *fuse.AttrO
 		n.fs.reportFailure(fuseOpGetattr, fmt.Errorf("%s: %v", fuseOpGetattr, err))
 		return syscall.EIO
 	}
-	entryToAttr(ino, n.attr, &out.Attr)
+	n.entryToAttr(ino, n.attr, &out.Attr)
 	return 0
 }
 
@@ -594,7 +598,7 @@ func (f *file) Getattr(ctx context.Context, out *fuse.AttrOut) syscall.Errno {
 		f.n.fs.reportFailure(fuseOpFileGetattr, fmt.Errorf("%s: %v", fuseOpFileGetattr, err))
 		return syscall.EIO
 	}
-	entryToAttr(ino, f.n.attr, &out.Attr)
+	f.n.entryToAttr(ino, f.n.attr, &out.Attr)
 	return 0
 }
 
@@ -797,7 +801,7 @@ func (sf *statFile) updateStatUnlocked() ([]byte, error) {
 }
 
 // entryToAttr converts metadata.Attr to go-fuse's Attr.
-func entryToAttr(ino uint64, e metadata.Attr, out *fuse.Attr) fusefs.StableAttr {
+func (n *node) entryToAttr(ino uint64, e metadata.Attr, out *fuse.Attr) fusefs.StableAttr {
 	out.Ino = ino
 	out.Size = uint64(e.Size)
 	if e.Mode&os.ModeSymlink != 0 {
@@ -808,7 +812,9 @@ func entryToAttr(ino uint64, e metadata.Attr, out *fuse.Attr) fusefs.StableAttr
 	mtime := e.ModTime
 	out.SetTimes(nil, &mtime, nil)
 	out.Mode = fileModeToSystemMode(e.Mode)
-	out.Owner = fuse.Owner{Uid: uint32(e.UID), Gid: uint32(e.GID)}
+	// Potentially dangerous casting int -> uint32? But probably fine.
+	mappedId, _ := n.idMapper.ToHost(idtools.User{Uid: uint32(e.UID), Gid: uint32(e.GID)})
+	out.Owner = fuse.Owner{Uid: mappedId.Uid, Gid: mappedId.Gid}
 	out.Rdev = uint32(unix.Mkdev(uint32(e.DevMajor), uint32(e.DevMinor)))
 	out.Nlink = uint32(e.NumLink)
 	if out.Nlink == 0 {
diff --git a/fs/layer/node_test.go b/fs/layer/node_test.go
index 432b3b66e..9f12e6810 100644
--- a/fs/layer/node_test.go
+++ b/fs/layer/node_test.go
@@ -50,7 +50,8 @@ func TestEntryToAttr(t *testing.T) {
 		tc := tc
 		t.Run(tc.name, func(t *testing.T) {
 			var actual fuse.Attr
-			entryToAttr(0, tc.attr, &actual)
+			var n node
+			n.entryToAttr(0, tc.attr, &actual)
 			tc.expected.Mtime = actual.Mtime
 			if actual != tc.expected {
 				t.Fatalf("unexpected fuse attr. actual %v expected %v", actual, tc.expected)
diff --git a/fs/layer/util_test.go b/fs/layer/util_test.go
index 2271f5556..c6134308e 100644
--- a/fs/layer/util_test.go
+++ b/fs/layer/util_test.go
@@ -56,6 +56,7 @@ import (
 	"github.com/awslabs/soci-snapshotter/fs/reader"
 	"github.com/awslabs/soci-snapshotter/fs/remote"
 	spanmanager "github.com/awslabs/soci-snapshotter/fs/span-manager"
+	"github.com/awslabs/soci-snapshotter/idtools"
 	"github.com/awslabs/soci-snapshotter/metadata"
 	"github.com/awslabs/soci-snapshotter/util/testutil"
 	"github.com/awslabs/soci-snapshotter/ztoc"
@@ -362,7 +363,7 @@ func hasSize(name string, size int) check {
 }
 
 func getRootNode(t *testing.T, r reader.Reader, opaque OverlayOpaqueType) *node {
-	rootNode, err := newNode(testStateLayerDigest, &testReader{r}, &testBlobState{10, 5}, 100, opaque, false, nil)
+	rootNode, err := newNode(testStateLayerDigest, &testReader{r}, &testBlobState{10, 5}, 100, opaque, false, nil, idtools.IDMap{})
 	if err != nil {
 		t.Fatalf("failed to get root node: %v", err)
 	}
diff --git a/fs/source/source.go b/fs/source/source.go
index ce394d840..9da0b36b2 100644
--- a/fs/source/source.go
+++ b/fs/source/source.go
@@ -84,6 +84,9 @@ const (
 
 	// TargetSociIndexDigestLabel is a label which contains the digest of the soci index.
 	TargetSociIndexDigestLabel = "containerd.io/snapshot/remote/soci.index.digest"
+
+	// HasSociIndexDigest is a label that tells if the layer was pulled with a SOCI index.
+	HasSociIndexDigest = "containerd.io/snapshot/remote/has.soci.index.digest"
 )
 
 // RegistryHosts is copied from [github.com/awslabs/soci-snapshotter/service/resolver.RegistryHosts]
diff --git a/go.mod b/go.mod
index c0f49bdd3..a95db767b 100644
--- a/go.mod
+++ b/go.mod
@@ -27,6 +27,7 @@ require (
 	github.com/prometheus/client_golang v1.20.4
 	github.com/rs/xid v1.6.0
 	github.com/sirupsen/logrus v1.9.3
+	github.com/stretchr/testify v1.9.0
 	go.etcd.io/bbolt v1.3.11
 	golang.org/x/crypto v0.27.0
 	golang.org/x/sync v0.8.0
@@ -90,7 +91,6 @@ require (
 	github.com/prometheus/common v0.55.0 // indirect
 	github.com/prometheus/procfs v0.15.1 // indirect
 	github.com/spf13/pflag v1.0.5 // indirect
-	github.com/stretchr/testify v1.9.0 // indirect
 	go.opencensus.io v0.24.0 // indirect
 	go.opentelemetry.io/contrib/instrumentation/net/http/otelhttp v0.45.0 // indirect
 	go.opentelemetry.io/otel v1.21.0 // indirect
diff --git a/idtools/idmap.go b/idtools/idmap.go
index be34a0f0e..9e82ec5a8 100644
--- a/idtools/idmap.go
+++ b/idtools/idmap.go
@@ -34,9 +34,17 @@
 package idtools
 
 import (
+	"context"
+	"encoding/json"
 	"errors"
 	"fmt"
+	"os"
+	"os/exec"
+	"path/filepath"
+	"syscall"
 
+	"github.com/containerd/containerd/mount"
+	"github.com/containerd/containerd/snapshots"
 	"github.com/opencontainers/runtime-spec/specs-go"
 )
 
@@ -60,6 +68,21 @@ type IDMap struct {
 	GidMap []specs.LinuxIDMapping `json:"GidMap"`
 }
 
+func LoadIdMap(id string, labels map[string]string) (IDMap, error) {
+	var idmap IDMap
+	uidmapJson, okUid := labels[snapshots.LabelSnapshotUIDMapping]
+	gidmapJson, okGid := labels[snapshots.LabelSnapshotGIDMapping]
+	if okUid && okGid {
+		if err := json.Unmarshal([]byte(uidmapJson), &idmap.UidMap); err != nil {
+			return IDMap{}, err
+		}
+		if err := json.Unmarshal([]byte(gidmapJson), &idmap.GidMap); err != nil {
+			return IDMap{}, err
+		}
+	}
+	return idmap, nil
+}
+
 // ToHost returns the host user ID pair for the container ID pair.
 func (i IDMap) ToHost(pair User) (User, error) {
 	var (
@@ -113,3 +136,48 @@ func safeSum(x, y uint32) (uint32, error) {
 	}
 	return z, nil
 }
+
+func RemapDir(ctx context.Context, originalMountpoint, newMountpoint string, idMap IDMap) error {
+	idmappedSnapshotBase := filepath.Dir(newMountpoint)
+	if err := os.Mkdir(idmappedSnapshotBase, 0755); err != nil {
+		return err
+	}
+
+	if err := exec.Command("cp", "-R", originalMountpoint, idmappedSnapshotBase).Run(); err != nil {
+		// if err := continuity.CopyDir(newMountpoint, originalMountpoint); err != nil {
+		return err
+	}
+	return filepath.Walk(newMountpoint, chown(idMap))
+}
+
+func RemapRoot(ctx context.Context, root string, idMap IDMap) error {
+	return filepath.Walk(root, chown(idMap))
+}
+
+func RemapRootFS(ctx context.Context, mounts []mount.Mount, idmap IDMap) error {
+	return mount.WithTempMount(ctx, mounts, func(root string) error {
+		return filepath.Walk(root, chown(idmap))
+	})
+}
+
+func chown(idMap IDMap) filepath.WalkFunc {
+	return func(path string, info os.FileInfo, err error) error {
+		if err != nil {
+			return err
+		}
+		stat := info.Sys().(*syscall.Stat_t)
+		h, cerr := idMap.ToHost(User{Uid: stat.Uid, Gid: stat.Gid})
+		if cerr != nil {
+			return cerr
+		}
+		// be sure the lchown the path as to not de-reference the symlink to a host file
+		if cerr = os.Lchown(path, int(h.Uid), int(h.Gid)); cerr != nil {
+			return cerr
+		}
+		// we must retain special permissions such as setuid, setgid and sticky bits
+		if mode := info.Mode(); mode&os.ModeSymlink == 0 && mode&(os.ModeSetuid|os.ModeSetgid|os.ModeSticky) != 0 {
+			return os.Chmod(path, mode)
+		}
+		return nil
+	}
+}
diff --git a/integration/run_test.go b/integration/run_test.go
index 260eb7a56..dc7bb72db 100644
--- a/integration/run_test.go
+++ b/integration/run_test.go
@@ -37,6 +37,7 @@ import (
 	"bytes"
 	"fmt"
 	"os"
+	"path/filepath"
 	"regexp"
 	"strconv"
 	"strings"
@@ -520,3 +521,132 @@ func TestRunInNamespace(t *testing.T) {
 		}
 	}
 }
+
+func TestRunWithIdMap(t *testing.T) {
+	tests := []struct {
+		name           string
+		imageName      string
+		indexBuilderFn func(sh *shell.Shell, src imageInfo, opts ...indexBuildOption) string
+		remapUser      string
+		remapGroup     string
+		remapUid       string
+		remapGid       string
+		checkLocation  string
+		expectedOwner  string
+	}{
+		{
+			name:      "with only FUSE layers",
+			imageName: rabbitmqImage,
+			indexBuilderFn: func(sh *shell.Shell, src imageInfo, opts ...indexBuildOption) string {
+				opts = append(opts, withMinLayerSize(0))
+				return buildIndex(sh, src, opts...)
+			},
+			remapUser:     "dummy-user",
+			remapGroup:    "dummy-group",
+			remapUid:      "123456",
+			remapGid:      "123456",
+			checkLocation: "usr",
+			expectedOwner: "123456",
+		},
+		{
+			name:      "with mixed layers",
+			imageName: rabbitmqImage,
+			indexBuilderFn: func(sh *shell.Shell, src imageInfo, opts ...indexBuildOption) string {
+				return buildIndex(sh, src, opts...)
+			},
+			remapUser:     "dummy-user",
+			remapGroup:    "dummy-group",
+			remapUid:      "123456",
+			remapGid:      "123456",
+			checkLocation: "usr",
+			expectedOwner: "123456",
+		},
+		{
+			name:      "with no SOCI index",
+			imageName: rabbitmqImage,
+			indexBuilderFn: func(sh *shell.Shell, src imageInfo, opts ...indexBuildOption) string {
+				return ""
+			},
+			remapUser:     "dummy-user",
+			remapGroup:    "dummy-group",
+			remapUid:      "123456",
+			remapGid:      "123456",
+			checkLocation: "usr",
+			expectedOwner: "123456",
+		},
+	}
+
+	baseSnapshotDir := "/var/lib/soci-snapshotter-grpc/snapshotter/snapshots"
+	baseRuntimeDir := "/run/containerd/io.containerd.runtime.v2.task/default"
+	testContainerName := "testidmap"
+	uidPath := "/etc/subuid"
+	gidPath := "/etc/subgid"
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			regConfig := newRegistryConfig()
+			sh, done := newShellWithRegistry(t, regConfig)
+			defer done()
+
+			sh.X("groupadd", "-g", tt.remapGid, tt.remapGroup)
+			sh.X("useradd", "-u", tt.remapUid, "-g", tt.remapGid, "-m", tt.remapUser)
+
+			subUidFile := fmt.Sprintf("%s:%s:%s", tt.remapUser, tt.remapUid, "1000")
+			subGidFile := fmt.Sprintf("%s:%s:%s", tt.remapUser, tt.remapGid, "1000")
+			sh.Pipe(nil, shell.C("echo", subUidFile), shell.C("tee", uidPath))
+			sh.Pipe(nil, shell.C("echo", subGidFile), shell.C("tee", gidPath))
+
+			rebootContainerd(t, sh, "", getSnapshotterConfigToml(t, false))
+			imageInfo := dockerhub(tt.imageName)
+			sh.X("nerdctl", "pull", "-q", tt.imageName)
+
+			filenames, err := sh.OLog("ls", baseSnapshotDir)
+			if err != nil {
+				t.Fatalf("error listing files in %s", baseSnapshotDir)
+			}
+
+			// Copy image, remove blobs, and re-pull with SOCI
+			copyImage(sh, dockerhub(tt.imageName), regConfig.mirror(tt.imageName))
+			indexDigest := tt.indexBuilderFn(sh, regConfig.mirror(tt.imageName))
+			if indexDigest != "" {
+				sh.X("soci", "push", "--user", regConfig.creds(), regConfig.mirror(tt.imageName).ref)
+			}
+			sh.X("rm", "-rf", filepath.Join(store.DefaultSociContentStorePath, "blobs", "sha256"))
+
+			pullCmd := imagePullCmd
+			if indexDigest != "" {
+				pullCmd = append(pullCmd, "--soci-index-digest", indexDigest)
+			}
+			sh.X(append(pullCmd, regConfig.mirror(tt.imageName).ref)...)
+			// time.Sleep(999999999999999999)
+			sh.X("ctr-with-idmapping", "run", "-d",
+				"--remap-labels",
+				"--userns-remap", tt.remapUser,
+				"--snapshotter", "soci",
+				imageInfo.ref, testContainerName, "sleep", "infinity",
+			)
+
+			newFilenames, err := sh.OLog("ls", baseSnapshotDir)
+			if err != nil {
+				t.Fatalf("error listing files in %s", baseSnapshotDir)
+			}
+
+			if len(filenames) == len(newFilenames) {
+				t.Fatalf("error: id-mapping failed")
+			}
+
+			fullCheckPath := filepath.Join(baseRuntimeDir, testContainerName, "rootfs", tt.checkLocation)
+			stat, err := sh.OLog("stat", fullCheckPath)
+			if err != nil {
+				t.Fatalf("error stat files in %s", fullCheckPath)
+			}
+
+			strStat := string(stat)
+			t.Log(strStat)
+			matchUid := fmt.Sprintf("Uid: (%s", tt.expectedOwner)
+			if !strings.Contains(strStat, matchUid) {
+				t.Fatalf("error: file %s did not have uid %s", tt.checkLocation, tt.expectedOwner)
+			}
+		})
+	}
+}
diff --git a/service/service.go b/service/service.go
index 167168e09..f627508d4 100644
--- a/service/service.go
+++ b/service/service.go
@@ -119,6 +119,9 @@ func NewSociSnapshotterService(ctx context.Context, root string, serviceCfg *con
 	if serviceCfg.SnapshotterConfig.AllowInvalidMountsOnRestart {
 		snOpts = append(snOpts, snbase.AllowInvalidMountsOnRestart)
 	}
+	if serviceCfg.FSConfig.AllowIdMap {
+		snOpts = append(snOpts, snbase.AllowIdMap)
+	}
 
 	snapshotter, err = snbase.NewSnapshotter(ctx, snapshotterRoot(root), fs, snOpts...)
 	if err != nil {
diff --git a/snapshot/snapshot.go b/snapshot/snapshot.go
index f770b5b5b..a0bc004c6 100644
--- a/snapshot/snapshot.go
+++ b/snapshot/snapshot.go
@@ -44,6 +44,7 @@ import (
 
 	commonmetrics "github.com/awslabs/soci-snapshotter/fs/metrics/common"
 	"github.com/awslabs/soci-snapshotter/fs/source"
+	"github.com/awslabs/soci-snapshotter/idtools"
 	"github.com/containerd/containerd/mount"
 	ctdsnapshotters "github.com/containerd/containerd/pkg/snapshotters"
 	"github.com/containerd/containerd/snapshots"
@@ -104,7 +105,10 @@ type FileSystem interface {
 	Mount(ctx context.Context, mountpoint string, labels map[string]string) error
 	Check(ctx context.Context, mountpoint string, labels map[string]string) error
 	Unmount(ctx context.Context, mountpoint string) error
+	UnmountLocal(ctx context.Context, mountpoint string) error
 	MountLocal(ctx context.Context, mountpoint string, labels map[string]string, mounts []mount.Mount) error
+	IdMapMount(ctx context.Context, mountpoint, activeLayerKey string, idmap idtools.IDMap) (string, error)
+	IdMapMountLocal(ctx context.Context, mountpoint, activeLayerKey string, idmap idtools.IDMap) (string, error)
 }
 
 // SnapshotterConfig is used to configure the remote snapshotter instance
@@ -113,6 +117,7 @@ type SnapshotterConfig struct {
 	// minLayerSize skips remote mounting of smaller layers
 	minLayerSize                int64
 	allowInvalidMountsOnRestart bool
+	allowIdMap                  bool
 }
 
 // Opt is an option to configure the remote snapshotter
@@ -140,6 +145,11 @@ func AllowInvalidMountsOnRestart(config *SnapshotterConfig) error {
 	return nil
 }
 
+func AllowIdMap(config *SnapshotterConfig) error {
+	config.allowIdMap = true
+	return nil
+}
+
 type snapshotter struct {
 	root        string
 	ms          *storage.MetaStore
@@ -150,6 +160,8 @@ type snapshotter struct {
 	userxattr                   bool  // whether to enable "userxattr" mount option
 	minLayerSize                int64 // minimum layer size for remote mounting
 	allowInvalidMountsOnRestart bool
+	allowIdMap                  bool
+	idmapped                    map[string]interface{}
 }
 
 // NewSnapshotter returns a Snapshotter which can use unpacked remote layers
@@ -200,6 +212,8 @@ func NewSnapshotter(ctx context.Context, root string, targetFs FileSystem, opts
 		userxattr:                   userxattr,
 		minLayerSize:                config.minLayerSize,
 		allowInvalidMountsOnRestart: config.allowInvalidMountsOnRestart,
+		allowIdMap:                  config.allowIdMap,
+		idmapped:                    make(map[string]interface{}),
 	}
 
 	if err := o.restoreRemoteSnapshot(ctx); err != nil {
@@ -285,6 +299,48 @@ func (o *snapshotter) Usage(ctx context.Context, key string) (snapshots.Usage, e
 	return usage, nil
 }
 
+func (o *snapshotter) setupIdMap(ctx context.Context, s storage.Snapshot, parent string, labels map[string]string) error {
+	// load id-map if appropriate labels are present.
+	idmap, err := idtools.LoadIdMap(s.ID, labels)
+	if err != nil {
+		log.G(ctx).Errorf("failed to load id-map: %v", err)
+		return err
+	}
+
+	if !idmap.Empty() {
+		parentSnapshot, err := o.Stat(ctx, parent)
+		if err != nil {
+			log.G(ctx).Errorf("failed to stat parent snapshot: %v", err)
+			return err
+		}
+
+		// If there is no SOCI index, you can safely mount from the root without copying over every single layer
+		if _, ok := parentSnapshot.Labels[source.HasSociIndexDigest]; !ok {
+			// Fallback to overlay
+			log.G(ctx).Info("no SOCI index found, remapping from root")
+			mounts, err := o.mounts(ctx, s, parent)
+			if err != nil {
+				return err
+			}
+
+			err = idtools.RemapRootFS(ctx, mounts, idmap)
+			if err != nil {
+				return err
+			}
+		} else {
+			o.idmapped[s.ID] = struct{}{}
+			err = o.createIdMapMounts(ctx, s, idmap)
+			if err != nil {
+				log.G(ctx).Errorf("failed to create id-mapped mounts: %v", err)
+				return err
+			}
+		}
+
+		log.G(ctx).Info("id-mapping successful")
+	}
+	return nil
+}
+
 func (o *snapshotter) Prepare(ctx context.Context, key, parent string, opts ...snapshots.Opt) ([]mount.Mount, error) {
 	log.G(ctx).WithField("key", key).WithField("parent", parent).Debug("prepare")
 	s, err := o.createSnapshot(ctx, snapshots.KindActive, key, parent, opts)
@@ -302,7 +358,15 @@ func (o *snapshotter) Prepare(ctx context.Context, key, parent string, opts ...s
 	}
 
 	target, ok := base.Labels[targetSnapshotLabel]
+	// !ok means we are in an active snapshot
 	if !ok {
+		// Setup id-mapped mounts if config allows.
+		// Any error here needs to stop the container from starting.
+		if o.allowIdMap {
+			if err := o.setupIdMap(ctx, s, parent, base.Labels); err != nil {
+				return nil, err
+			}
+		}
 		return o.mounts(ctx, s, parent)
 	}
 
@@ -319,7 +383,8 @@ func (o *snapshotter) Prepare(ctx context.Context, key, parent string, opts ...s
 	if !o.skipRemoteSnapshotPrepare(lCtx, base.Labels) {
 		err := o.prepareRemoteSnapshot(lCtx, key, base.Labels)
 		if err == nil {
-			base.Labels[remoteLabel] = remoteLabelVal // Mark this snapshot as remote
+			base.Labels[remoteLabel] = remoteLabelVal       // Mark this snapshot as remote
+			base.Labels[source.HasSociIndexDigest] = "true" // Mark that this snapshot was loaded with a SOCI index
 			err := o.commit(ctx, true, target, key, append(opts, snapshots.WithLabels(base.Labels))...)
 			if err == nil || errdefs.IsAlreadyExists(err) {
 				// count also AlreadyExists as "success"
@@ -361,6 +426,7 @@ func (o *snapshotter) Prepare(ctx context.Context, key, parent string, opts ...s
 	log.G(ctx).WithField("layerDigest", base.Labels[ctdsnapshotters.TargetLayerDigestLabel]).Info("preparing snapshot as local snapshot")
 	err = o.prepareLocalSnapshot(lCtx, key, base.Labels, mounts)
 	if err == nil {
+		base.Labels[source.HasSociIndexDigest] = "true" // Mark that this snapshot was loaded with a SOCI index
 		err := o.commit(ctx, false, target, key, append(opts, snapshots.WithLabels(base.Labels))...)
 		if err == nil || errdefs.IsAlreadyExists(err) {
 			// count also AlreadyExists as "success"
@@ -578,7 +644,13 @@ func (o *snapshotter) getCleanupDirectories(ctx context.Context, t storage.Trans
 	cleanup := []string{}
 	for _, d := range dirs {
 		if !cleanupCommitted {
-			if _, ok := ids[d]; ok {
+			currDir := d
+			// Use the id-mapped suffix if present
+			temp := strings.Split(d, "_")
+			if len(temp) > 1 {
+				currDir = temp[1]
+			}
+			if _, ok := ids[currDir]; ok {
 				continue
 			}
 		}
@@ -613,7 +685,10 @@ func (o *snapshotter) unmountSnapshotDirectory(ctx context.Context, dir string)
 		return err
 	}
 	if mounted {
-		return o.fs.Unmount(ctx, mp)
+		if err := o.fs.Unmount(ctx, mp); err == errdefs.ErrNotFound {
+			return o.fs.UnmountLocal(ctx, mp)
+		}
+		return err
 	}
 	return nil
 }
@@ -757,15 +832,16 @@ func (o *snapshotter) mounts(ctx context.Context, s storage.Snapshot, checkKey s
 		}, nil
 	}
 
-	parentPaths := make([]string, len(s.ParentIDs))
-	for i := range s.ParentIDs {
-		parentPaths[i] = o.upperPath(s.ParentIDs[i])
+	parentPaths, err := o.getParentPaths(ctx, s)
+	if err != nil {
+		return nil, err
 	}
 
 	options = append(options, fmt.Sprintf("lowerdir=%s", strings.Join(parentPaths, ":")))
 	if o.userxattr {
 		options = append(options, "userxattr")
 	}
+
 	return []mount.Mount{
 		{
 			Type:    "overlay",
@@ -773,7 +849,50 @@ func (o *snapshotter) mounts(ctx context.Context, s storage.Snapshot, checkKey s
 			Options: options,
 		},
 	}, nil
+}
+
+func (o *snapshotter) getParentPaths(ctx context.Context, s storage.Snapshot) ([]string, error) {
+	parentPaths := make([]string, len(s.ParentIDs))
+
+	for i := range s.ParentIDs {
+		id := s.ParentIDs[i]
+		if _, ok := o.idmapped[s.ID]; ok {
+			id = fmt.Sprintf("%s_%s", s.ParentIDs[i], s.ID)
+		}
+		parentPaths[i] = o.upperPath(id)
+	}
+
+	return parentPaths, nil
+}
+
+func (o *snapshotter) createIdMapMounts(ctx context.Context, s storage.Snapshot, idmap idtools.IDMap) error {
+	log.G(ctx).Infof("mapping ids")
+
+	for _, id := range s.ParentIDs {
+		err := o.createIdMapMount(ctx, o.upperPath(id), s.ID, idmap)
+		if err != nil {
+			return err
+		}
+	}
 
+	return idtools.RemapRoot(ctx, o.upperPath(s.ID), idmap)
+}
+
+func (o *snapshotter) createIdMapMount(ctx context.Context, path, id string, idmap idtools.IDMap) error {
+	// s.ID is the shortest unique identifier for each new container,
+	// so append it to the end of the new mountpoint
+	_, err := o.fs.IdMapMount(ctx, path, id, idmap)
+	if err == errdefs.ErrNotFound {
+		// Remote mount failed, attempt to create a local id-mapped mount
+
+		// Cleanup dirty snapshot folder — perhaps we can have a return cleanup func?
+		dirtyDir := fmt.Sprintf("%s_%s", filepath.Dir(path), id)
+		if err := os.RemoveAll(dirtyDir); err != nil {
+			return err
+		}
+		_, err = o.fs.IdMapMountLocal(ctx, path, id, idmap)
+	}
+	return err
 }
 
 // upperPath produces a file path like "{snapshotter.root}/snapshots/{id}/fs"
diff --git a/snapshot/snapshot_test.go b/snapshot/snapshot_test.go
index cc798a607..6ee794d5b 100644
--- a/snapshot/snapshot_test.go
+++ b/snapshot/snapshot_test.go
@@ -41,6 +41,7 @@ import (
 	"syscall"
 	"testing"
 
+	"github.com/awslabs/soci-snapshotter/idtools"
 	"github.com/containerd/containerd/mount"
 	"github.com/containerd/containerd/pkg/testutil"
 	"github.com/containerd/containerd/snapshots"
@@ -406,6 +407,9 @@ func (fs *bindFs) Check(ctx context.Context, mountpoint string, labels map[strin
 func (fs *bindFs) Unmount(ctx context.Context, mountpoint string) error {
 	return syscall.Unmount(mountpoint, 0)
 }
+func (fs *bindFs) UnmountLocal(ctx context.Context, mountpoint string) error {
+	return errdefs.ErrNotImplemented
+}
 
 func (fs *bindFs) MountLocal(ctx context.Context, mountpoint string, labels map[string]string, mounts []mount.Mount) error {
 	if _, ok := labels[brokenLabel]; ok {
@@ -417,6 +421,14 @@ func (fs *bindFs) MountLocal(ctx context.Context, mountpoint string, labels map[
 	return nil
 }
 
+func (fs *bindFs) IdMapMount(ctx context.Context, mountpoint, activeLayerKey string, idmap idtools.IDMap) (string, error) {
+	return mountpoint, nil
+}
+
+func (fs *bindFs) IdMapMountLocal(ctx context.Context, mountpoint, activeLayerKey string, idmap idtools.IDMap) (string, error) {
+	return mountpoint, nil
+}
+
 func dummyFileSystem() FileSystem { return &dummyFs{} }
 
 type dummyFs struct{}
@@ -433,10 +445,22 @@ func (fs *dummyFs) Unmount(ctx context.Context, mountpoint string) error {
 	return fmt.Errorf("dummy")
 }
 
+func (fs *dummyFs) UnmountLocal(ctx context.Context, mountpoint string) error {
+	return fmt.Errorf("dummy")
+}
+
 func (fs *dummyFs) MountLocal(ctx context.Context, mountpoint string, labels map[string]string, mounts []mount.Mount) error {
 	return fmt.Errorf("dummy")
 }
 
+func (fs *dummyFs) IdMapMount(ctx context.Context, mountpoint, activeLayerKey string, idmap idtools.IDMap) (string, error) {
+	return "", fmt.Errorf("dummy")
+}
+
+func (fs *dummyFs) IdMapMountLocal(ctx context.Context, mountpoint, activeLayerKey string, idmap idtools.IDMap) (string, error) {
+	return "", fmt.Errorf("dummy")
+}
+
 // =============================================================================
 // Tests backword-comaptibility of overlayfs snapshotter.