The whole area of software engineering environments is an emerging one. Such environments have become necessary due to the rapid changes which have occurred in the software industry in the last twenty years. The desire is to produce products of high quality and at a reasonable cost. Unfortunately history shows that, in general, software systems rarely met the specific need for which they were developed and were often unreliable, inefficient , poorly documented and required considerable maintenance. One of the main areas of research into increasing both the productivity and the quality of software has been the use of software engineering environments. The area of software engineering environments is a changing one with evolving definitions. What can be stated is that a key objective of software engineering environments is the support of software process from requirements definition through to system maintenance. Such support can only be provided through the development of integrated sets of tools each supporting various aspects of the software development process. In order for tools to be fully integrated and have the same ’look and feel’ it is necessary that they are developed on a common platform, providing all the facilities needed for tool development and integration. Such a platform is the Eclipse tool builder’s kit based on the Portable Common Tool Environment (PCTE). The work in this thesis was based on an evaluation of this development platform for developing and integrating software tools, particularly real-time telecommunications software tools. The work in this thesis was carried out as part of the European Community’s RACE programme. The project was called SPECS 1. The SPECS project is outlined in chapter one of this thesis along with a brief history of the research into software engineering environments to date. The work which I was responsible for involved both the integration of existing toolsets and tools, developed by other partners in the SPECS project, as well as the development of new "native" tools within Eclipse/PCTE. This work was necessary so that the SPECS project could produce an integrated set of tools at the end of its research. It was my job to evaluate the potential of Eclipse/PCTE as a basis for this integration.