ReqPat: Efficient Documentation of High-quality Requirements using Controlled Natural Language The growing complexity of today's software intensive systems results in an increased size of requirements specifications, which are typically documented by means of natural language (NL). Large NL requirements specifications are prone to contain defects (e.g., contradictions), and the inherent ambiguity of NL impedes automatic techniques to support the requirements engineer. In order to cope with this problem, we conceived a requirements documentation approach implemented in the tool ReqPat. Using a controlled NL, it supports an efficient requirements documentation, an automatic requirements validation, and an automatic transition to models--while still keeping the requirements understandable for all stakeholders. IEEE