A pilot study which is part of both a larger provincial initiative and a network is in progress to address the question of genetic pre-disposition to non-polyposis colorectal cancer in eastern Ontario (population 1,200,000). It is modeled along a dual process of recruitment of at-risk individuals based on either prior documentation of family histories or a close relationship to patients who are hospitalized for colorectal cancer treatment. The molecular diagnostic and genetic counseling components of the project are in their initial phase of operation while follow-up strategies are being planned.