The Oil Sands Upgrader in northern Alberta, Canada, built by OPTI Canada, was one of Canada's largest Foundation Fieldbus installations when it came on-stream in 2007. The design and specification of the instruments and controls are a joint effort among three design-engineering contractors (DEC), and Automation Contractor (GAC) (aligned with the DCS vendor) and the Owner (OPTI). Some detailed design work for the DECs and the FAC was also performed in India. This paper describes the development of specifications, drawings and guidelines and the preparation of studies required to justify the use of Foundation Fieldbus. The process used, the pitfalls encountered, and the progress made in the selection of suitable DCS suppliers and automation contractors are covered. The lessons learned in the many discussions with Foundation Fieldbus experts, FF users, and FF instrument suppliers are discussed in detail. The interaction and interfaces between the DECs and the GAC in the project organization and the work splits between the GAC, DEC and the DEC's offices in India is explained.