Abstract. Matching descriptions of user requirements against descriptions of service capabilities is crucial for the discovery of appropriate services for a given task. To improve the precision of approaches that consider only syntactical aspects of matchmaking (e.g. UDDI) several approaches for semantic matchmaking have been proposed. We compare two approaches with respect to their potentials for matchmaking between semantic descriptions of geoinformation services. The State-based Approach uses the Web Ontology Language and the Rule Markup Language to describe inputs, outputs, preconditions and effects. In the Algebraic Approach, abstract data types are specified to capture domain knowledge. The specific data types used in a service model referred to these shared concepts. In order to make the specifications executable and to enable matchmaking a functional programming language (Haskell) is used in this approach. For a scenario from the domain of disaster management, both approaches are tested for one specific type of match. 1