Evren Sirin is a Semantic Web researcher focusing on the areas of automated reasoning for Web ontologies, Description Logic (DL) reasoning, composition of Web Services and AI planning. He joined Clark & Parsia in September 2006 after getting his PhD degree from Computer Science department of University of Maryland, College Park.

At the University of Maryland, Evren was a graduate research assistant at the MINDSWAP research group directed by Jim Hendler. He worked in close collaboration with Bijan Parsia and they co-authored many technical papers on the Semantic Web. During his graduate study, Evren also developed various tools for the Semantic Web including the popular OWL-DL reasoner Pellet which is now being commercially supported by C&P.

Evren's research at MINDSWAP mostly focused on combining DL reasoning and AI planning techniques to automate the composition of Web Services. His research was closely related to and in large funded by the Task Computing project of Fujitsu Labs of America, College Park. Evren also participated in the standardization efforts of Semantic Web Services as a member of the OWL-S coalition and contributed to the development of OWL-S ontologies. He also developed several tools based on OWL-S such as the software library OWL-S API and the Web Service composer, one of the first prototypes that demonstrated the semi-automated composition of Web Services.