Abstract: Server-side scripting for creating customized documents for clients is disclosed. A server application processes code included in a script, causing the server application to issue a request to a decision engine to select content that is designated as appropriate for a client based on attributes of the client. The request is issued to the decision engine without the server application indicating the decision criteria that are to be used or the particular attributes of the client on which the selection is to be based. The decision engine uses the appropriate decision criteria and selects content for the document from content files associated with the decision engine. The decision engine can instead select further portions of script from the content files, which are processed by the server application and result in additional decisions being made by the decision engine.