During the last years, the emergence of Semantic Web has produced a vast amount of resources and a variety of content representation schemes. The latter has increased the complexity that the users are facing when searching for information in open environments. A representative example is Electronic Markets (EMs). In EMs users try to find and purchase products through interactions with providers. In such scenarios, shopbots can offer a number of advantages. Shopbots are agents that help users to find the products they want, saving them a lot of time and effort. However, building efficient shopbots is a challenging task. This is more imperative when shopbots interact with providers using different ontological terms for product description. In this chapter, the authors propose a generic ontology to describe products in EMs. They also introduce a matching algorithm that maps the specific provider ontology to the generic one in order to be used by a shopbot. Their algorithm, called S+, is based on a set of linguistic and semantic matching techniques. The authors present their approach and compare it with other proposed algorithms. Finally, they discuss their experimental results that reveal the performance of their methodology.