diff --git a/DEVELOPER.md b/DEVELOPER.md
index 2809df0638f8..241d6dda992d 100644
--- a/DEVELOPER.md
+++ b/DEVELOPER.md
@@ -26,6 +26,10 @@ refreshenv
 
 You must run `Developing the Provider` commands in `bash` because `sh` scrips are invoked as part of these.
 
+You may hit issues with `make build` telling you every file needs to be formatted as a result of line endings. To avoid this issue set your git config using `git config --global core.autocrlf false`. This will tell git to use the source `LF` rather than the Windows default of `CRLF`.
+
+You may get errors when cloning the repository on Windows that end with `Filename too long`. To avoid this issue set your git config using `git config --system core.longpaths true`. This will tell git to allow file names longer than 260 characters which is the default on Windows.
+
 ## Developing the Provider
 
 If you wish to work on the provider, you'll first need [Go](http://www.golang.org) installed on your machine. You'll also need to correctly setup a [GOPATH](http://golang.org/doc/code.html#GOPATH), as well as adding `$GOPATH/bin` to your `$PATH`.
diff --git a/internal/services/policy/policy_definition_data_source.go b/internal/services/policy/policy_definition_data_source.go
index 4cb9df72cbf5..6d42227f76d9 100644
--- a/internal/services/policy/policy_definition_data_source.go
+++ b/internal/services/policy/policy_definition_data_source.go
@@ -79,6 +79,11 @@ func dataSourceArmPolicyDefinition() *pluginsdk.Resource {
 					Type: pluginsdk.TypeString,
 				},
 			},
+
+			"mode": {
+				Type:     pluginsdk.TypeString,
+				Computed: true,
+			},
 		},
 	}
 }
@@ -122,6 +127,7 @@ func dataSourceArmPolicyDefinitionRead(d *pluginsdk.ResourceData, meta interface
 	d.Set("description", policyDefinition.Description)
 	d.Set("type", policyDefinition.Type)
 	d.Set("policy_type", policyDefinition.PolicyType)
+	d.Set("mode", policyDefinition.Mode)
 
 	policyRule := policyDefinition.PolicyRule.(map[string]interface{})
 	if policyRuleStr := flattenJSON(policyRule); policyRuleStr != "" {
diff --git a/internal/services/policy/policy_definition_data_source_test.go b/internal/services/policy/policy_definition_data_source_test.go
index 8dd60b978d1f..bb1b89e7b140 100644
--- a/internal/services/policy/policy_definition_data_source_test.go
+++ b/internal/services/policy/policy_definition_data_source_test.go
@@ -23,6 +23,7 @@ func TestAccDataSourceAzureRMPolicyDefinition_builtIn(t *testing.T) {
 				check.That(data.ResourceName).Key("display_name").HasValue("Allowed resource types"),
 				check.That(data.ResourceName).Key("type").HasValue("Microsoft.Authorization/policyDefinitions"),
 				check.That(data.ResourceName).Key("description").HasValue("This policy enables you to specify the resource types that your organization can deploy. Only resource types that support 'tags' and 'location' will be affected by this policy. To restrict all resources please duplicate this policy and change the 'mode' to 'All'."),
+				check.That(data.ResourceName).Key("mode").HasValue("Indexed"),
 			),
 		},
 	})
@@ -56,6 +57,7 @@ func TestAccDataSourceAzureRMPolicyDefinition_builtInByName(t *testing.T) {
 				check.That(data.ResourceName).Key("display_name").HasValue("Allowed resource types"),
 				check.That(data.ResourceName).Key("type").HasValue("Microsoft.Authorization/policyDefinitions"),
 				check.That(data.ResourceName).Key("description").HasValue("This policy enables you to specify the resource types that your organization can deploy. Only resource types that support 'tags' and 'location' will be affected by this policy. To restrict all resources please duplicate this policy and change the 'mode' to 'All'."),
+				check.That(data.ResourceName).Key("mode").HasValue("Indexed"),
 			),
 		},
 	})
@@ -90,6 +92,7 @@ func TestAccDataSourceAzureRMPolicyDefinition_customByDisplayName(t *testing.T)
 				check.That(data.ResourceName).Key("policy_rule").HasValue("{\"if\":{\"not\":{\"field\":\"location\",\"in\":\"[parameters('allowedLocations')]\"}},\"then\":{\"effect\":\"audit\"}}"),
 				check.That(data.ResourceName).Key("parameters").HasValue("{\"allowedLocations\":{\"type\":\"Array\",\"metadata\":{\"description\":\"The list of allowed locations for resources.\",\"displayName\":\"Allowed locations\",\"strongType\":\"location\"}}}"),
 				check.That(data.ResourceName).Key("metadata").Exists(),
+				check.That(data.ResourceName).Key("mode").HasValue("All"),
 			),
 		},
 	})
@@ -110,6 +113,7 @@ func TestAccDataSourceAzureRMPolicyDefinition_customByName(t *testing.T) {
 				check.That(data.ResourceName).Key("policy_rule").HasValue("{\"if\":{\"not\":{\"field\":\"location\",\"in\":\"[parameters('allowedLocations')]\"}},\"then\":{\"effect\":\"audit\"}}"),
 				check.That(data.ResourceName).Key("parameters").HasValue("{\"allowedLocations\":{\"type\":\"Array\",\"metadata\":{\"description\":\"The list of allowed locations for resources.\",\"displayName\":\"Allowed locations\",\"strongType\":\"location\"}}}"),
 				check.That(data.ResourceName).Key("metadata").Exists(),
+				check.That(data.ResourceName).Key("mode").HasValue("All"),
 			),
 		},
 	})
diff --git a/website/docs/d/policy_definition.html.markdown b/website/docs/d/policy_definition.html.markdown
index b4ed35775357..900e10c62587 100644
--- a/website/docs/d/policy_definition.html.markdown
+++ b/website/docs/d/policy_definition.html.markdown
@@ -50,6 +50,8 @@ output "id" {
 
 * `metadata` - Any Metadata defined in the Policy.
 
+* `mode` - The Mode of the Policy.
+
 ## Timeouts
 
 The `timeouts` block allows you to specify [timeouts](https://www.terraform.io/language/resources/syntax#operation-timeouts) for certain actions: