A method (200) of operation in a communication system (100) when a mobile node (107) is served in a network (103, 105) which is not its home network (101). The mobile node: (a) when attached to a first service node (117) identifies (203) a second service node (123) as a candidate service node to which it can become attached by an attachment handover procedure; (b) obtains (205) a new Care Of Address for use in association with attachment of the mobile node to the second service node; (c) notifies (207) the second service node of its identity and of its new Care Of Address; and (d) notifies (213) a Home Agent for the mobile node of the identity of the second service node and/or of the new Care Of Address.