diff --git a/src/applications/drydock/worker/DrydockLeaseUpdateWorker.php b/src/applications/drydock/worker/DrydockLeaseUpdateWorker.php
--- a/src/applications/drydock/worker/DrydockLeaseUpdateWorker.php
+++ b/src/applications/drydock/worker/DrydockLeaseUpdateWorker.php
@@ -666,6 +666,26 @@
     DrydockLease $lease) {
     $viewer = $this->getViewer();
 
+    // If this lease is marked as already in the process of reclaiming a
+    // resource, don't let it reclaim another one until the first reclaim
+    // completes. This stops one lease from reclaiming a large number of
+    // resources if the reclaims take a while to complete.
+    $reclaiming_phid = $lease->getAttribute('drydock.reclaimingPHID');
+    if ($reclaiming_phid) {
+      $reclaiming_resource = id(new DrydockResourceQuery())
+        ->setViewer($viewer)
+        ->withPHIDs(array($reclaiming_phid))
+        ->withStatuses(
+          array(
+            DrydockResourceStatus::STATUS_ACTIVE,
+            DrydockResourceStatus::STATUS_RELEASED,
+          ))
+        ->executeOne();
+      if ($reclaiming_resource) {
+        return null;
+      }
+    }
+
     $resources = id(new DrydockResourceQuery())
       ->setViewer($viewer)
       ->withBlueprintPHIDs(array($blueprint->getPHID()))
diff --git a/src/applications/drydock/worker/DrydockWorker.php b/src/applications/drydock/worker/DrydockWorker.php
--- a/src/applications/drydock/worker/DrydockWorker.php
+++ b/src/applications/drydock/worker/DrydockWorker.php
@@ -241,16 +241,25 @@
     DrydockLease $lease) {
     $viewer = $this->getViewer();
 
+    // Mark the lease as reclaiming this resource. It won't be allowed to start
+    // another reclaim as long as this resource is still in the process of
+    // being reclaimed.
+    $lease->setAttribute('drydock.reclaimingPHID', $resource->getPHID());
+
     // When the resource releases, we we want to reawaken this task since it
-    // should be able to start building a new resource right away.
+    // should (usually) be able to start building a new resource right away.
     $worker_task_id = $this->getCurrentWorkerTaskID();
 
     $command = DrydockCommand::initializeNewCommand($viewer)
       ->setTargetPHID($resource->getPHID())
       ->setAuthorPHID($lease->getPHID())
       ->setCommand(DrydockCommand::COMMAND_RECLAIM)
-      ->setProperty('awakenTaskIDs', array($worker_task_id))
-      ->save();
+      ->setProperty('awakenTaskIDs', array($worker_task_id));
+
+    $lease->openTransaction();
+      $lease->save();
+      $command->save();
+    $lease->saveTransaction();
 
     $resource->scheduleUpdate();