This paper presents a visual application in the framework of semantic-enabled e-marketplaces aimed at fully exploiting semantics of supply/demand descriptions in B2C and C2C e-marketplaces. Distinguishing aspects of the framework include logic-based explanation of request results, semantic ranking of matchmaking results, logic-based request refinement. The visual user interface has been designed and implemented to be immediate and simple, and it requires no knowledge of any logic principle to be fully used. Categories and Subject Descriptors H.4.2 [Information Systems Applications]: Decision Support; I.2.4 [Knowledge Representation Formalisms and Methods]: Representation languages General Terms Algorithms, Languages, Economics Keywords Semantic Web, Matchmaking, E-marketplaces