diff --git a/rackspace/db/v1/instances/requests.go b/rackspace/db/v1/instances/requests.go
index a0ffcad..60775dd 100644
--- a/rackspace/db/v1/instances/requests.go
+++ b/rackspace/db/v1/instances/requests.go
@@ -19,3 +19,22 @@
 
 	return res
 }
+
+func AssociateWithConfigGroup(client *gophercloud.ServiceClient, instanceID, configGroupID string) UpdateResult {
+	reqBody := map[string]string{
+		"configuration": configGroupID,
+	}
+
+	var res UpdateResult
+
+	resp, err := perigee.Request("PUT", resourceURL(client, instanceID), perigee.Options{
+		MoreHeaders: client.AuthenticatedHeaders(),
+		ReqBody:     map[string]map[string]string{"instance": reqBody},
+		OkCodes:     []int{202},
+	})
+
+	res.Header = resp.HttpResponse.Header
+	res.Err = err
+
+	return res
+}