This book addresses the problem of benchmarking semantic web technologies; first, from a methodological point of view, proposing a general methodology to follow in benchmarking activities over semantic web technologies and, second, from a practical point of view, presenting two international benchmarking activities that involved benchmarking the interoperability of semantic web technologies using RDF(S) as the interchange language in one activity and OWL in the other. The book presents in detail how the different resources needed for these interoperability benchmarking activities were defined: the experiments, the benchmark suites and the software that support the process. Furthermore, the book invites practitioners to reach a continuous improvement of semantic technologies by means of their continuous evaluation and presents future lines of research.