diff --git a/src/Identity/v3/Models/Catalog.php b/src/Identity/v3/Models/Catalog.php
index d208d7b6..a4957243 100644
--- a/src/Identity/v3/Models/Catalog.php
+++ b/src/Identity/v3/Models/Catalog.php
@@ -31,6 +31,44 @@ public function populateFromArray(array $data): self
         return $this;
     }
 
+    /**
+     * Retrieve a base URL for a service, according to its catalog name, type, region.
+     *
+     * @param string $name      the name of the service as it appears in the catalog
+     * @param string $type      the type of the service as it appears in the catalog
+     * @param string $region    the region of the service as it appears in the catalog
+     * @param string $interface the interface of the service as it appears in the catalog
+     *
+     * @return null|string NULL if no URL found
+     */
+    public function getServiceUrlOverride(
+        string $name,
+        string $type,
+        string $region,
+        string $interface,
+        array $overrides
+    ): ?string {
+        foreach ($overrides as $override) {
+            if (
+                (empty($override['name']) || $name == $override['name'])
+                && (empty($override['type']) || $type == $override['type'])
+                && (empty($override['region']) || $region == $override['region'])
+                && (empty($override['interface']) || $interface == $override['interface'])
+            ) {
+                if (empty($override['name']) && empty($override['type'])) {
+                    throw new \RuntimeException(sprintf("Endpoint override must at least specify an \"url\" and either \"name\" or a \"type\"."));
+                }
+                if (empty($override['url'])) {
+                    throw new \RuntimeException(sprintf("Endpoint override must specify an \"url\".\nName: %s\nType: %s\nRegion: %s\nInterface: %s", $override['name'] ?? '', $override['type'] ?? '', $override['region'] ?? '', $override['interface'] ?? ''));
+                }
+
+                return $override['url'];
+            }
+        }
+
+        return null;
+    }
+
     /**
      * Retrieve a base URL for a service, according to its catalog name, type, region.
      *
diff --git a/src/Identity/v3/Service.php b/src/Identity/v3/Service.php
index 5760436f..407cd9cb 100644
--- a/src/Identity/v3/Service.php
+++ b/src/Identity/v3/Service.php
@@ -47,6 +47,18 @@ public function authenticate(array $options): array
         $region    = $options['region'];
         $interface = $options['interface'] ?? Enum::INTERFACE_PUBLIC;
 
+        if (!empty($options['catalog_overrides'])) {
+            $baseUrl = $token->catalog->getServiceUrlOverride(
+                $name,
+                $type,
+                $region,
+                $interface,
+                $options['catalog_overrides']
+            );
+            if ($baseUrl) {
+                return [$token, $baseUrl];
+            }
+        }
         if ($baseUrl = $token->catalog->getServiceUrl($name, $type, $region, $interface)) {
             return [$token, $baseUrl];
         }