User interfaces are normally based on low-level trickery either within the run-time system, or in a separate program which has been connected to the stream I/O system of the language. We present a new twist to this by giving some intelligence to the outside system, which will have greater control of the interface. This has a number of benefits: it makescreating new programs easier, increasesthe efficiency of the resulting system, and improves the separation between the two halves of the system. 1 Introduction Many people have written of the problems functional languages have with user interfaces, and have proposed various solutions. These solutions range from the simplistic [9], to the powerful [10], with some truly innovative possibilities explored [4,5]. These systems usually have, at some level, the functional program communicating with an external system, receiving events from the user or system, and replying with requests, telling the system what to do next. This can be done eith...