Provide endpoint discovery via closure for v3.
diff --git a/endpoint_search.go b/endpoint_search.go
new file mode 100644
index 0000000..eea89e8
--- /dev/null
+++ b/endpoint_search.go
@@ -0,0 +1,32 @@
+package gophercloud
+
+import "errors"
+
+var (
+	// ErrEndpointNotFound is returned when no available endpoints match the provided EndpointOpts.
+	ErrEndpointNotFound = errors.New("No suitable endpoint could be found in the service catalog.")
+)
+
+// EndpointOpts contains options for finding an endpoint for an Openstack client.
+type EndpointOpts struct {
+
+	// Type is the service type for the client (e.g., "compute", "object-store").
+	// Type is a required field.
+	Type string
+
+	// Name is the service name for the client (e.g., "nova").
+	// Name is not a required field, but it is used if present.
+	// Services can have the same Type but a different Name, which is one example of when both Type and Name are needed.
+	Name string
+
+	// Region is the region in which the service resides.
+	Region string
+
+	// URLType is they type of endpoint to be returned (e.g., "public", "private").
+	// URLType is not required, and defaults to "public".
+	URLType string
+}
+
+// EndpointLocator is a function that describes how to locate a single endpoint from a service catalog for a specific ProviderClient.
+// It should be set during ProviderClient initialization and used to discover related ServiceClients.
+type EndpointLocator func(EndpointOpts) (string, error)