diff --git a/.travis.yml b/.travis.yml
index e2e865967..97e8bb977 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -49,6 +49,7 @@ script:
   - source ${BLT_DIR}/scripts/travis/run_tests
   - source ${BLT_DIR}/scripts/blt/ci/internal/doctor.sh
   - phpunit ${BLT_DIR}/tests/phpunit --group blt-project -c ${BLT_DIR}/tests/phpunit/phpunit.xml
+  - phpunit ${BLT_DIR}/tests/phpunit --group blt-multisite -c ${BLT_DIR}/tests/phpunit/phpunit.xml
   # Deploy build artifact.
   - blt deploy:build
   - source ${BLT_DIR}/scripts/blt/ci/internal/test_artifact.sh
diff --git a/phing/build.yml b/phing/build.yml
index 965e22c3e..47baf3450 100644
--- a/phing/build.yml
+++ b/phing/build.yml
@@ -85,11 +85,13 @@ git:
     pre-commit: ${blt.root}/scripts/git-hooks
     commit-msg: ${blt.root}/scripts/git-hooks
 
-multisite:
-  # The docroot/sites/default directory is used by default.
-  name:
-    - default
-    # - another_site
+# You may provide a list of sites for BLT to run commands against,
+# otherwise BLT will generate this sites list based on directories
+# in ${docroot}/sites/*/
+#
+# multisite:
+#  name:
+#    - default
 
 reports:
   localDir: ${repo.root}/reports
diff --git a/phing/tasks/properties.xml b/phing/tasks/properties.xml
index 66f323ac1..718fd48b3 100644
--- a/phing/tasks/properties.xml
+++ b/phing/tasks/properties.xml
@@ -56,6 +56,18 @@
     </then>
   </if>
 
+  <if>
+    <not>
+      <isset property="multisite.name"/>
+    </not>
+    <!-- Build the sites list if not specified by the user. -->
+    <then>
+    <!-- Find directories in ${docroot}/sites/*/ and format into a comma-separated list. -->
+    <exec command="find ${docroot}/sites/* -maxdepth 0 -type d | sed -e 's%${docroot}/sites/%%g' -e '2,$s%^%,%' | tr -d '\n'"
+          outputProperty="multisite.name" logoutput="false" checkreturn="true"/>
+    </then>
+  </if>
+
   <if>
     <!-- There is multisite config. Allow it to override default values. -->
     <available file="${blt.config-files.multisite}" />
diff --git a/tests/phpunit/BltProject/PropertiesTest.php b/tests/phpunit/BltProject/PropertiesTest.php
new file mode 100644
index 000000000..85905cdda
--- /dev/null
+++ b/tests/phpunit/BltProject/PropertiesTest.php
@@ -0,0 +1,65 @@
+<?php
+
+namespace Acquia\Blt\Tests\BltProject;
+
+use Acquia\Blt\Tests\BltProjectTestBase;
+
+/**
+ * Class PropertiesTest.
+ *
+ * Verifies that Phing properties are being parsed as expected.
+ */
+class PropertiesTest extends BltProjectTestBase {
+
+  /**
+   * Tests whether multisite.name is parsed as expected.
+   *
+   * @group blt-multisite
+   */
+  public function testMultisiteProperties() {
+    $this->assertPropertyEquals('multisite.name', BLT_MULTISITE_NAME);
+  }
+
+  /**
+   * Asserts that a given property has an expected value.
+   *
+   * @param string $property
+   *    The property to check.
+   * @param string $expected
+   *    The expected value of $property.
+   * @param string $site
+   *    An optional site name.
+   */
+  protected function assertPropertyEquals($property, $expected, $site = '') {
+    $value = $this->getProperty($property, $site);
+    $this->assertEquals($expected, $value,
+      "Expected value at $property to equal '$expected'. Instead, $property equals '$value'.");
+  }
+
+  /**
+   * Gets the value a given property (optionally specifying a site).
+   *
+   * @param string $property
+   *    The property to check.
+   * @param string $site
+   *    An optional site name.
+   *
+   * @return string
+   *    The value of $property.
+   */
+  private function getProperty($property, $site = '') {
+    $output = [];
+    $blt_bin = $this->projectDirectory . '/vendor/bin/blt';
+    exec(
+    // Run the echo-property task (optionally providing a site name)
+    // and parse its output.
+      "$blt_bin echo-property -Dproperty.name=$property " . (!empty($site) ? "-Dmultisite.name=$site" : "") .
+      // Run command with minimal output and console styling.
+      " -emacs -silent", $output
+    );
+    // Property value will be output to the 1st line.
+    // Return an empty string if $property does not exist.
+    return !empty($output[0]) ? $output[0] : '';
+  }
+
+}
diff --git a/tests/phpunit/phpunit.xml b/tests/phpunit/phpunit.xml
index 40aecaaad..9454138c4 100644
--- a/tests/phpunit/phpunit.xml
+++ b/tests/phpunit/phpunit.xml
@@ -5,6 +5,7 @@
     <php>
         <const name="BLT_ENV" value="ci"/>
         <const name="BLT_ALIAS" value="self"/>
+        <const name="BLT_MULTISITE_NAME" value="default,g"/>
     </php>
 
 </phpunit>