As Web Services and the Semantic Web become more important, enabling technologies such as web service ontologies will grow larger. At the same time, use of mobile devices to access web services has doubled in the last year. The ability of these resource constrained devices to download and reason across these ontologies to support service discovery will be severely limited. Since concrete agents typically only needs a subset of what is described in a web service ontology to complete their task, a reduced ontology can be created. In this research, we define computable measures of quality and performance with respect to reduced ontologies. Using these measures, we developed a dynamic algorithm to generate a reduced ontology that contains the necessary knowledge content and performance speedup to be used by a mobile device for service discovery. [The dissertation citations contained here are published with the permission of ProQuest LLC. Further reproduction is prohibited without permission. Copies of dissertations may be obtained by Telephone (800) 1-800-521-0600. Web page: http://www.proquest.com/en-US/products/dissertations/individuals.shtml.]