A surveillance method and system is provided for receiving image data from a plurality of said cameras; storing the received image data identifying each camera from which the image data originated; enabling each of a plurality of camera users who own or operate respective cameras to assign a said camera owned or operated by the camera user to at least one said set of cameras and to authorize selected users of the system to access image data from said at least one set of cameras, wherein said users of the system can include camera users and/or users not owning or operating any cameras; storing camera set data identifying the assigned camera as belonging to said set of cameras; storing user data identifying the users authorized to access image data from said set of cameras; and outputting image data to users dependent upon said camera set data and said user data.