diff --git a/openstack/common/extensions/testing/fixtures.go b/openstack/common/extensions/testing/fixtures.go
new file mode 100644
index 0000000..a986c95
--- /dev/null
+++ b/openstack/common/extensions/testing/fixtures.go
@@ -0,0 +1,90 @@
+package testing
+
+import (
+	"fmt"
+	"net/http"
+	"testing"
+
+	"github.com/gophercloud/gophercloud/openstack/common/extensions"
+	th "github.com/gophercloud/gophercloud/testhelper"
+	"github.com/gophercloud/gophercloud/testhelper/client"
+)
+
+// ListOutput provides a single page of Extension results.
+const ListOutput = `
+{
+	"extensions": [
+		{
+			"updated": "2013-01-20T00:00:00-00:00",
+			"name": "Neutron Service Type Management",
+			"links": [],
+			"namespace": "http://docs.openstack.org/ext/neutron/service-type/api/v1.0",
+			"alias": "service-type",
+			"description": "API for retrieving service providers for Neutron advanced services"
+		}
+	]
+}`
+
+// GetOutput provides a single Extension result.
+const GetOutput = `
+{
+	"extension": {
+		"updated": "2013-02-03T10:00:00-00:00",
+		"name": "agent",
+		"links": [],
+		"namespace": "http://docs.openstack.org/ext/agent/api/v2.0",
+		"alias": "agent",
+		"description": "The agent management extension."
+	}
+}
+`
+
+// ListedExtension is the Extension that should be parsed from ListOutput.
+var ListedExtension = extensions.Extension{
+	Updated:     "2013-01-20T00:00:00-00:00",
+	Name:        "Neutron Service Type Management",
+	Links:       []interface{}{},
+	Namespace:   "http://docs.openstack.org/ext/neutron/service-type/api/v1.0",
+	Alias:       "service-type",
+	Description: "API for retrieving service providers for Neutron advanced services",
+}
+
+// ExpectedExtensions is a slice containing the Extension that should be parsed from ListOutput.
+var ExpectedExtensions = []extensions.Extension{ListedExtension}
+
+// SingleExtension is the Extension that should be parsed from GetOutput.
+var SingleExtension = &extensions.Extension{
+	Updated:     "2013-02-03T10:00:00-00:00",
+	Name:        "agent",
+	Links:       []interface{}{},
+	Namespace:   "http://docs.openstack.org/ext/agent/api/v2.0",
+	Alias:       "agent",
+	Description: "The agent management extension.",
+}
+
+// HandleListExtensionsSuccessfully creates an HTTP handler at `/extensions` on the test handler
+// mux that response with a list containing a single tenant.
+func HandleListExtensionsSuccessfully(t *testing.T) {
+	th.Mux.HandleFunc("/extensions", func(w http.ResponseWriter, r *http.Request) {
+		th.TestMethod(t, r, "GET")
+		th.TestHeader(t, r, "X-Auth-Token", client.TokenID)
+
+		w.Header().Add("Content-Type", "application/json")
+
+		fmt.Fprintf(w, ListOutput)
+	})
+}
+
+// HandleGetExtensionSuccessfully creates an HTTP handler at `/extensions/agent` that responds with
+// a JSON payload corresponding to SingleExtension.
+func HandleGetExtensionSuccessfully(t *testing.T) {
+	th.Mux.HandleFunc("/extensions/agent", func(w http.ResponseWriter, r *http.Request) {
+		th.TestMethod(t, r, "GET")
+		th.TestHeader(t, r, "X-Auth-Token", client.TokenID)
+
+		w.Header().Add("Content-Type", "application/json")
+		w.WriteHeader(http.StatusOK)
+
+		fmt.Fprintf(w, GetOutput)
+	})
+}