Abstract: A client/server system serves imagery to users with speed, efficiency, and desirable functionality. Clients are allocated the means to determine the image data necessary to generate views on an image. The clients issue requests for such necessary image data to servers who service the requests and send requested image data to the clients who then generate the views. The system responds quickly to changes of views resulting form user actions such as panning or zooming by enabling clients to determine which image data is needed that has not already been served and requesting service of only that data. Clients are also enabled to issue requests to cancel service of data previously requested, but unserved and no longer needed.