diff --git a/rackspace/db/v1/instances/fixtures.go b/rackspace/db/v1/instances/fixtures.go
index cbd18da..bbf578b 100644
--- a/rackspace/db/v1/instances/fixtures.go
+++ b/rackspace/db/v1/instances/fixtures.go
@@ -164,3 +164,16 @@
 `)
 	})
 }
+
+func HandleAssociateGroupSuccessfully(t *testing.T, id string) {
+	th.Mux.HandleFunc("/instances/"+id, func(w http.ResponseWriter, r *http.Request) {
+		th.TestMethod(t, r, "PUT")
+		th.TestHeader(t, r, "X-Auth-Token", fake.TokenID)
+		th.TestJSONRequest(t, r, `{"instance": {"configuration": "{configGroupID}"}}`)
+
+		w.WriteHeader(http.StatusAccepted)
+		w.Header().Add("Content-Type", "application/json")
+
+		fmt.Fprintf(w, singleInstanceJson)
+	})
+}
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
+}
diff --git a/rackspace/db/v1/instances/requests_test.go b/rackspace/db/v1/instances/requests_test.go
index e653c07..c746b6a 100644
--- a/rackspace/db/v1/instances/requests_test.go
+++ b/rackspace/db/v1/instances/requests_test.go
@@ -11,9 +11,9 @@
 	th.SetupHTTP()
 	defer th.TeardownHTTP()
 
-	HandleGetConfigSuccessfully(t)
+	HandleGetConfigSuccessfully(t, instanceID)
 
-	config, err := GetConfig(fake.ServiceClient(), opts).Extract()
+	config, err := GetDefaultConfig(fake.ServiceClient(), instanceID).Extract()
 
 	expected := map[string]string{
 		"basedir":                      "/usr",
@@ -63,3 +63,14 @@
 	th.AssertNoErr(t, err)
 	th.AssertDeepEquals(t, expected, config)
 }
+
+func TestAssociateWithConfigGroup(t *testing.T) {
+	th.SetupHTTP()
+	defer th.TeardownHTTP()
+
+	HandleAssociateGroupSuccessfully(t, instanceID)
+
+	configGroupID := "{configGroupID}"
+	res := AssociateWithConfigGroup(fake.ServiceClient(), instanceID, configGroupID)
+	th.AssertNoErr(t, res.Err)
+}
diff --git a/rackspace/db/v1/instances/results.go b/rackspace/db/v1/instances/results.go
index 2b7f4fd..c2c68e1 100644
--- a/rackspace/db/v1/instances/results.go
+++ b/rackspace/db/v1/instances/results.go
@@ -59,8 +59,8 @@
 }
 
 func (r ConfigResult) Extract() (map[string]string, error) {
-	if err != nil {
-		return nil, err
+	if r.Err != nil {
+		return nil, r.Err
 	}
 
 	var response struct {
@@ -69,6 +69,10 @@
 		} `mapstructure:"instance"`
 	}
 
-	err = mapstructure.Decode(body, &response)
-	return &response.Instance, err
+	err := mapstructure.Decode(r.Body, &response)
+	return response.Instance.Config, err
+}
+
+type UpdateResult struct {
+	gophercloud.ErrResult
 }
diff --git a/rackspace/db/v1/instances/urls.go b/rackspace/db/v1/instances/urls.go
index c0c1bad..12f8d83 100644
--- a/rackspace/db/v1/instances/urls.go
+++ b/rackspace/db/v1/instances/urls.go
@@ -10,6 +10,10 @@
 	return baseURL(c)
 }
 
-func configURL(c *gophercloud.ServiceClient) string {
+func resourceURL(c *gophercloud.ServiceClient, id string) string {
+	return c.ServiceURL("instances", id)
+}
+
+func configURL(c *gophercloud.ServiceClient, id string) string {
 	return c.ServiceURL("instances", id, "configuration")
 }