diff --git a/.travis.yml b/.travis.yml
index 98456efc6..01a859a4b 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -42,7 +42,10 @@ jobs:
     - { name: "Isolated test w/ dev package versions", env: ORCA_JOB=ISOLATED_DEV }
     - { name: "Integrated test w/ dev package versions", env: ORCA_JOB=INTEGRATED_DEV }
     - { name: "Integrated test w/ dev package versions & next minor dev version of Drupal core", env: ORCA_JOB=CORE_NEXT }
+    - { name: "D9 readiness test", php: "7.3", env: ORCA_JOB=D9_READINESS }
     - { name: "Custom job", env: ORCA_JOB=CUSTOM ORCA_CUSTOM_FIXTURE_INIT_ARGS="--help" ORCA_CUSTOM_TESTS_RUN_ARGS="--help" }
+  allow_failures:
+    - { php: "7.3", env: ORCA_JOB=D9_READINESS }
 
 before_install:
   - ../orca/bin/travis/self-test/before_install.sh
diff --git a/bin/travis/install.sh b/bin/travis/install.sh
index 8b7531b2b..6eaeee104 100755
--- a/bin/travis/install.sh
+++ b/bin/travis/install.sh
@@ -22,5 +22,6 @@ case "$ORCA_JOB" in
   "ISOLATED_DEV") orca debug:packages CURRENT_DEV; eval "orca fixture:init -f --sut=$ORCA_SUT_NAME --sut-only --core=CURRENT_DEV --dev --profile=$ORCA_FIXTURE_PROFILE" ;;
   "INTEGRATED_DEV") orca debug:packages CURRENT_DEV; eval "orca fixture:init -f --sut=$ORCA_SUT_NAME --core=CURRENT_DEV --dev --profile=$ORCA_FIXTURE_PROFILE" ;;
   "CORE_NEXT") orca debug:packages NEXT_DEV; eval "orca fixture:init -f --sut=$ORCA_SUT_NAME --core=NEXT_DEV --dev --profile=$ORCA_FIXTURE_PROFILE" ;;
+  "D9_READINESS") orca debug:packages D9_READINESS; eval "orca fixture:init -f --sut=$ORCA_SUT_NAME --sut-only --core='~9' --dev --profile=$ORCA_FIXTURE_PROFILE" ;;
   "CUSTOM") eval "orca fixture:init -f --sut=$ORCA_SUT_NAME --profile=$ORCA_FIXTURE_PROFILE ${ORCA_CUSTOM_FIXTURE_INIT_ARGS:=}" ;;
 esac
diff --git a/example/.travis.yml b/example/.travis.yml
index 7a994b7b6..2505cbc7e 100644
--- a/example/.travis.yml
+++ b/example/.travis.yml
@@ -97,6 +97,7 @@ jobs:
     - { name: "Isolated test w/ dev package versions", env: ORCA_JOB=ISOLATED_DEV }
     - { name: "Integrated test w/ dev package versions", env: ORCA_JOB=INTEGRATED_DEV }
     - { name: "Integrated test w/ dev package versions & next minor dev version of Drupal core", env: ORCA_JOB=CORE_NEXT }
+    - { name: "D9 readiness test", php: "7.3", env: ORCA_JOB=D9_READINESS}
     # Custom testing needs involving only minor variations on the standard setup
     # can be achieved without custom scripting using the "CUSTOM" ORCA_JOB.
     # @see https://github.com/acquia/orca/blob/master/docs/advanced-usage.md#travis-ci-scripts
@@ -109,6 +110,8 @@ jobs:
     - env: ORCA_JOB=ISOLATED_DEV
     - env: ORCA_JOB=INTEGRATED_DEV
     - env: ORCA_JOB=CORE_NEXT
+    # You may need to allow the D9 readiness job to fail in the short term.
+    - { php: "7.3", env: ORCA_JOB=D9_READINESS }
 
 # Install ORCA and prepare the environment.
 before_install:
diff --git a/example/example.info.yml b/example/example.info.yml
index ebe0bf802..7514f12ea 100644
--- a/example/example.info.yml
+++ b/example/example.info.yml
@@ -3,3 +3,4 @@ type: module
 description: "Provides an example module for testing and illustration purposes."
 package: Other
 core: 8.x
+core_version_requirement: '^8 || ^9'
diff --git a/src/Command/Debug/DebugPackagesCommand.php b/src/Command/Debug/DebugPackagesCommand.php
index a4b8eb29a..29ce2bfba 100644
--- a/src/Command/Debug/DebugPackagesCommand.php
+++ b/src/Command/Debug/DebugPackagesCommand.php
@@ -105,6 +105,7 @@ public function execute(InputInterface $input, OutputInterface $output): int {
     }
 
     (new Table($output))
+      ->setHeaderTitle("Drupal {$this->coreVersion}")
       ->setHeaders($this->getHeaders())
       ->setRows($this->getRows())
       ->render();
@@ -120,8 +121,8 @@ public function execute(InputInterface $input, OutputInterface $output): int {
    * @SuppressWarnings(PHPMD.StaticAccess)
    */
   private function handleCoreArgument($argument): void {
-    if (is_null($argument)) {
-      return;
+    if ($argument === NULL) {
+      $argument = '*';
     }
 
     if (!is_string($argument)) {
diff --git a/src/Enum/DrupalCoreVersion.php b/src/Enum/DrupalCoreVersion.php
index 97a64aebb..083572ef4 100644
--- a/src/Enum/DrupalCoreVersion.php
+++ b/src/Enum/DrupalCoreVersion.php
@@ -21,6 +21,8 @@ final class DrupalCoreVersion extends Enum {
 
   public const NEXT_DEV = 'NEXT_DEV';
 
+  public const D9_READINESS = 'D9_READINESS';
+
   /**
    * Provides help text for commands that accept Drupal core version input.
    *
@@ -35,6 +37,7 @@ public static function commandHelp() {
       sprintf('- %s: The current development version, e.g., "8.6.x-dev"', self::CURRENT_DEV),
       sprintf('- %s: The next release version if available, e.g., "8.7.0-beta2"', self::NEXT_RELEASE),
       sprintf('- %s: The next development version, e.g., "8.7.x-dev"', self::NEXT_DEV),
+      sprintf('- %s: The current development version of Drupal 9, e.g., "9.0.x-dev"', self::D9_READINESS),
     ];
   }
 
diff --git a/src/Utility/DrupalCoreVersionFinder.php b/src/Utility/DrupalCoreVersionFinder.php
index ab445667a..eea3cc52b 100644
--- a/src/Utility/DrupalCoreVersionFinder.php
+++ b/src/Utility/DrupalCoreVersionFinder.php
@@ -66,6 +66,9 @@ public function get(DrupalCoreVersion $version): string {
       case DrupalCoreVersion::NEXT_DEV:
         return $this->getNextDevVersion();
 
+      case DrupalCoreVersion::D9_READINESS:
+        return $this->getD9DevVersion();
+
       default:
         throw new \LogicException(sprintf('Unknown version. Update %s:%s.', __CLASS__, __FUNCTION__));
     }
@@ -97,17 +100,20 @@ public function getPretty(DrupalCoreVersion $version): string {
    * @param string $minimum_stability
    *   The minimum stability. Available options (in order of stability) are
    *   dev, alpha, beta, RC, and stable.
+   * @param string $preferred_stability
+   *   The preferred stability. Available options (in order of stability) are
+   *   dev, alpha, beta, RC, and stable.
    *
    * @return string
    *   The version string.
    */
-  public function find(string $target_package_version = NULL, string $minimum_stability = 'stable'): string {
+  public function find(string $target_package_version = NULL, string $minimum_stability = 'stable', string $preferred_stability = 'stable'): string {
     $best_candidate = $this->getVersionSelector($minimum_stability)
-      ->findBestCandidate('drupal/core', $target_package_version);
+      ->findBestCandidate('drupal/core', $target_package_version, NULL, $preferred_stability);
     if (!$best_candidate) {
       throw new \RuntimeException(sprintf('No Drupal core version satisfies the given constraints: version=%s, minimum stability=%s', $target_package_version, $minimum_stability));
     }
-    return $best_candidate->getVersion();
+    return $best_candidate->getPrettyVersion();
   }
 
   /**
@@ -196,6 +202,18 @@ private function getNextDevVersion(): string {
     return "{$previous_minor_version}.x-dev";
   }
 
+  /**
+   * Gets the next D9 dev version.
+   *
+   * @return string
+   *   The version string, e.g., "9.0.x-dev".
+   *
+   * @see \Acquia\Orca\Enum\DrupalCoreVersion::D9_READINESS
+   */
+  private function getD9DevVersion(): string {
+    return $this->find('~9', 'dev', 'dev');
+  }
+
   /**
    * Gets a Composer version selector.
    *
diff --git a/tests/Command/Debug/DebugPackagesCommandTest.php b/tests/Command/Debug/DebugPackagesCommandTest.php
index f2b660574..00bb1dd7a 100644
--- a/tests/Command/Debug/DebugPackagesCommandTest.php
+++ b/tests/Command/Debug/DebugPackagesCommandTest.php
@@ -10,7 +10,6 @@
 use Acquia\Orca\Tests\Command\CommandTestBase;
 use Acquia\Orca\Utility\DrupalCoreVersionFinder;
 use Composer\Semver\VersionParser;
-use Prophecy\Argument;
 use Symfony\Component\Console\Command\Command;
 
 /**
@@ -43,8 +42,8 @@ public function testBasicExecution() {
     $package->getType()->willReturn('drupal-module');
     $package->getInstallPathRelative()->willReturn('docroot/modules/contrib/example1', 'docroot/modules/contrib/example2');
     $package->getRepositoryUrlRaw()->willReturn('../example1', '../example2');
-    $package->getVersionRecommended(NULL)->willReturn('~1.0');
-    $package->getVersionDev(NULL)->willReturn('1.x-dev');
+    $package->getVersionRecommended('*')->willReturn('~1.0');
+    $package->getVersionDev('*')->willReturn('1.x-dev');
     $package->shouldGetEnabled()->willReturn(TRUE);
     $this->packageManager
       ->getAll()
@@ -53,14 +52,14 @@ public function testBasicExecution() {
 
     $this->executeCommand();
 
-    $this->assertEquals(ltrim("
-+-----------+---------------+----------------------------------+-------------+---------+-------------+--------+
+    $this->assertEquals(ltrim('
++-----------+---------------+--------------------- Drupal * ---+-------------+---------+-------------+--------+
 | Package   | type          | install_path                     | url         | version | version_dev | enable |
 +-----------+---------------+----------------------------------+-------------+---------+-------------+--------+
 | Example 1 | drupal-module | docroot/modules/contrib/example1 | ../example1 | ~1.0    | 1.x-dev     | yes    |
 | Example 2 | drupal-module | docroot/modules/contrib/example2 | ../example2 | ~1.0    | 1.x-dev     | yes    |
 +-----------+---------------+----------------------------------+-------------+---------+-------------+--------+
-"), $this->getDisplay(), 'Displayed correct output.');
+'), $this->getDisplay(), 'Displayed correct output.');
     $this->assertEquals(StatusCode::OK, $this->getStatusCode(), 'Returned correct status code.');
   }
 
@@ -70,26 +69,13 @@ public function testBasicExecution() {
   public function testValidArguments($argument) {
     $version = '8.7.0.0';
     $this->drupalCoreVersionFinder
-      ->get(Argument::any())
+      ->get(new DrupalCoreVersion($argument))
       ->shouldBeCalledOnce()
       ->willReturn($version);
-    $package = $this->prophesize(Package::class);
-    $package->getPackageName()->willReturn('Example 1');
-    $package->getType()->willReturn('drupal-module');
-    $package->getInstallPathRelative()->willReturn('docroot/modules/contrib/example1');
-    $package->getRepositoryUrlRaw()->willReturn('../example1');
-    $package->getVersionRecommended($version)
-      ->shouldBeCalledOnce();
-    $package->getVersionDev($version)
-      ->shouldBeCalledOnce();
-    $this->packageManager
-      ->getAll()
-      ->shouldBeCalledOnce()
-      ->willReturn([$package]);
-    $package->shouldGetEnabled()->willReturn(TRUE);
 
     $this->executeCommand(['core' => $argument]);
 
+    $this->assertContains(ltrim("- Drupal {$version} -"), $this->getDisplay(), 'Displayed correct output.');
     $this->assertEquals(StatusCode::OK, $this->getStatusCode(), 'Returned correct status code.');
   }
 
@@ -108,7 +94,7 @@ public function testInvalidArguments($version) {
     $this->executeCommand(['core' => $version]);
 
     $error_message = sprintf('Error: Invalid value for "core" option: "%s".', $version) . PHP_EOL
-      . 'Hint: Acceptable values are "PREVIOUS_RELEASE", "PREVIOUS_DEV", "CURRENT_RECOMMENDED", "CURRENT_DEV", "NEXT_RELEASE", "NEXT_DEV", or any version string Composer understands.' . PHP_EOL;
+      . 'Hint: Acceptable values are "PREVIOUS_RELEASE", "PREVIOUS_DEV", "CURRENT_RECOMMENDED", "CURRENT_DEV", "NEXT_RELEASE", "NEXT_DEV", "D9_READINESS", or any version string Composer understands.' . PHP_EOL;
     $this->assertEquals($error_message, $this->getDisplay(), 'Displayed correct output.');
     $this->assertEquals(StatusCode::ERROR, $this->getStatusCode(), 'Returned correct status code.');
   }
diff --git a/tests/Command/Fixture/FixtureInitCommandTest.php b/tests/Command/Fixture/FixtureInitCommandTest.php
index ec307afe2..121c37a5e 100644
--- a/tests/Command/Fixture/FixtureInitCommandTest.php
+++ b/tests/Command/Fixture/FixtureInitCommandTest.php
@@ -259,7 +259,7 @@ public function testCoreOptionVersionParsing($status_code, $value, $display) {
 
   public function providerCoreOptionVersionParsing() {
     $error_message = 'Error: Invalid value for "--core" option: "%s".' . PHP_EOL
-      . 'Hint: Acceptable values are "PREVIOUS_RELEASE", "PREVIOUS_DEV", "CURRENT_RECOMMENDED", "CURRENT_DEV", "NEXT_RELEASE", "NEXT_DEV", or any version string Composer understands.' . PHP_EOL;
+      . 'Hint: Acceptable values are "PREVIOUS_RELEASE", "PREVIOUS_DEV", "CURRENT_RECOMMENDED", "CURRENT_DEV", "NEXT_RELEASE", "NEXT_DEV", "D9_READINESS", or any version string Composer understands.' . PHP_EOL;
     return [
       [StatusCode::OK, self::CORE_VALUE_LITERAL_PREVIOUS_RELEASE, ''],
       [StatusCode::OK, self::CORE_VALUE_LITERAL_CURRENT_RECOMMENDED, ''],