A group of researchers at Philips research labs in the UK have developed an Agent Behaviour Language, (ABLE), in which agents are programmed in terms of simple, rule-like licences [Wavish, 1992][Connah and Wavish, 1990]. Licences may include some representation of time (though the language is not based on any kind of temporal logic): they loosely resemble behaviours in the subsumption architecture (see above). ABLE can be compiled down to a simple digital machine, realised in the `C' programming language. The idea is similar to situated automata, though there appears to be no equivalent theoretical foundation. The result of the compilation process is a very fast implementation, which has been reportedly used to control a Compact Disk-Interactive (CD-I) application. ABLE has recently been extended to a version called Real-Time ABLE (RTA) [Wavish and Graham, 1994].