The increasing number of services available on the Web requires sophisticated mechanisms for the matchmaking, selection and composition of services based on business criteria. Such mechanisms require descriptions that address business terms, but existing approaches for the modeling of service properties are inadequate for expressing business conditions. In this paper, we propose a novel Service Description Language for Contract specification (SeDL-C). The proposal is based on a detailed analysis of business terms to identify the set of requirements a model and a language should fulfill. Formal syntax and semantics for SeDL-C are given.