AGENT0 was only ever intended as a prototype, to illustrate the principles of AOP. A more refined implementation was developed by Thomas, for her 1993 doctoral thesis [Thomas, 1993]. Her Planning Communicating Agents (PLACA) language was intended to address one severe drawback to AGENT0: the inability of agents to plan, and communicate requests for action via high-level goals. Agents in PLACA are programmed in much the same way as in AGENT0, in terms of mental change rules. The logical component of PLACA is similar to AGENT0's, but includes operators for planning to do actions and achieve goals. The semantics of the logic and its properties are examined in detail. However, PLACA is not at the `production' stage; it is an experimental language.