Panel discussion on Architectures for Tool Integration The software development process consists of a variety of interrelated phased. Each phase is supported by some methodology and specialized development tools. The variety of the activities as well as the low level interoperability among tools often discourage the co-operation of the teams involved in the development process. This causes high development costs and, moreover, the overall quality of the produced software is reduced by low orchestration support. Integration of existing development tools has been recognized as one part of the solution to this problem. The design of Integrated Development Environments and the definition of mechanisms for tool integration is still a challenging research issue for software engineering. Recently, a number of innovative technologies such us JXTA, .NET, SOAP, WEB and Grid Services have been developed. Although they have been designed for rather different purposes these technologies can be exploited for building integrated and extensible architectures of software development tools. The goal of this panel is to present and discuss on-going work and to set up a research agenda in this area. We will address two main questions. - Is there a sound conceptual basis for tool integration, - Which technologies better meet the demands of tool integration.