To address the new process of graduate attributes (GAs) assessment as required by the Canadian Engineering Accreditation Board (CEAB), the University of Waterloo (UW) employed six Graduate Attributes Lecturers (GALs) and four Accreditation Assistants (AAs) with a key role of leading the outcomes assessment process in each of the engineering departments. The GALs work collaboratively with each other and their departments to come up with a process of outcomes assessment. The collaboration methods and techniques used by the GALs in developing shared indicators for the common GAs are proving to be highly effective, and have led to significant progress. One of these methods is a structured brainstorming sessions for developing measurable performance indicators for the common GAs. The following paper describes in detail the collaboration methods and techniques used by the GALs and AAs to develop shared indicators for the professional skills GAs. The paper also discusses the factors that proved to be successful in the whole process as well as the challenges faced by the team.