This paper describes the joint approach of three research groups to enable a heterogeneous team of robots to exchange belief. The communication framework presented imposes little restrictions on the design and implementation of the individual autonomous mobile systems. The three groups have individually taken part in the RoboCup F2000 league since 1998. Although recent rule changes allow for more robots per team, the cost of acquiring and maintaining autonomous mobile robots keeps teams from making use of this opportunity. A solution is to build mixed teams with robots from different labs. As almost all robots in this league are custom built research platforms with unique sensors, actuators, and software architectures, forming a heterogeneous team presents an exciting challenge.