Multiprotocol systems are a vital tool for achieving interoperability in today's heterogeneous communication networks. An important aspect of these systems is the need to determine which of the multiple available protocols will be used to carry out a given communication task; an uninformed choice can result in failure to communicate when communication should be possible. In this document we consider ways to make information about hosts' supported protocol configurations available through the Domain Name System. We discuss various representation approaches, and describe their use with multiprotocol applications. We present the use of our approach with an example multiprotocol system incorporating IPng protocols.