So far there is very limited tool support for performance-oriented code development, software testing, and parameter studies of high-performance scientific applications. Such an effort commonly requires to conduct a large number of experimental executions. We have developed the ZENTURIO experiment management tool for multi-experimental parameter and performance studies of parallel and distributed applications on cluster and Grid architectures. We describe the design and implementation of ZENTURIO as a Grid application based on state-of-the-art Grid middleware technologies, such as Web services standards and the Globus toolkit. We offer solutions for building Open Grid Services Architecture-compliant Grid services using a pure Web services implementation toolkit. Existing Web services standards such as Universal Description Discovery and Integration and WSDL compatibility are refined for a more coherent integration with the Grid characteristics. We compare our design and implementation with an early prototype built on top of the OGSI technology. We report results on using ZENTURIO for performance study of a material science kernel and parameter study of a financial application.