Engineering students are required to have, by the time of graduation, a set of professional skills related to teamwork, oral and written communications, impact of engineering solutions, life-long learning, and knowledge of contemporary issues. Teaching and assessment of these skills, as part of ABET accreditation, remains problematic. A systematic methodology to integrate these skills and their assessment in the curriculum is described. The method was recently applied in several engineering programs and proved to be efficient in generating data and evidences for evaluation and continuous improvement of these outcomes.