Services deployed in a network computing environment (such as a Web services implementation model) are transparently extended. Preferably, handler components in an engine that processes requests and responses provide the extensions. A handler for outgoing messages adds the extensions to a response message that is created responsive to receiving a request message that asks for a service's available operations. A client receiving this response message can then invoke one of the extensions, without knowing that it is an extension. A handler for incoming messages checks received requests: if a request for an extension is received, the handler routes that message to a location other than the service itself; otherwise, incoming requests for operations that are actually available from the service are routed thereto. Extensions may provide additional operations such as, but not limited to, management operations, dynamic enabling/disabling of service operations, and/or controlled access to service operations--even though the service itself might contain no operations for these.