The MaTREx project will investigate techniques for analysing natural language requirements, in order to discover, manage, and mitigate the negative effects of tacit knowledge in requirements. Tacit knowledge is knowledge that we know we have but can't articulate, or knowledge that we don't know that we have but nevertheless use. We rely on tacit knowledge to communicate effectively: we need not make every assumption we hold explicit, allowing us to focus on the essence of what we wish to communicate. As engineers concerned with the development of software and systems, however, we are taught to make our assumptions explicit, and indeed any kind of knowledge that is not made explicit makes our systems analysis more difficult and error prone. This problem is particularly acute during requirements engineering (RE), when knowledge about the problem world and stakeholder requirements is elicited, and precise specifications of system structure and behaviour are developed. Requirements are often first communicated in natural language, and are often ambiguous, incomplete, and inevitably full of undocumented assumptions and other omissions. Effective analysis of such requirements needs to surface this tacit knowledge automatically or semi-automatically where possible to document more precise requirements that can be relied upon by stakeholders to communicate effectively. The project will adopt an empirical approach to characterise and elicit tacit knowledge, and a constructive, theoretically-grounded but user-driven approach to develop practical techniques and tools to guide analysts concerned with the development of precise requirements for software-intensive systems. The results will comprise tools and techniques for: improving the management of requirements information through automatic trace recovery; discovering the presence of tacit knowledge from the tracking of presuppositions and unprovenanced requirements; and the detection of nocuous ambiguity in requirements documents that imply potential for misinterpretation. The project is a collaboration between the Departments of Computing at The Open University (OU) and Lancaster University, and is funded the UK Engineering and Physical Sciences Research Council (EPSRC) The OU's share of the funding is £356,599, Lancaster's share is £252,245. The MaTREx project was the top ranked project at the EPSRC panel meeting in June 2008.