Abstract
The use of asynchronous communication is traditionally seen to be an important element of an agent’s autonomy. This paper argues that groups of agents within a society need the ability to choose forms of communication with stronger guarantees for particular interactions, and in particular, focuses on the use of reliable group communication. An example electronic trading scenario — the game of Pit — is presented, and it is shown how a formal institution for a particular critical phase of Pit can be built on top of the semantics for totally ordered and virtually synchronous multicasting.