The main ideas behind the implementation of the IALP RoboCup team are discussed: an agent architecture made of a hierarchy of behaviors, which can be combined to obtain different roles; a memory model which relies of the absolute positions of objects. The team is programmed using ECL, a Common Lisp implementation. The research goal that we are pursuing with IALP is twofold: (1) we want to show the flexibility and effectiveness of our agent architecture in the RoboCup domain and (2) we want to test ECL in a real time application.