This is an observational study based on a nationally representative, cross-sectional mailed survey of 3,744 male and female veterans age 50-75 who have had one or more primary care visits at a VA Medical facility in the past two years. The survey sample was drawn using a two stage procedure where we first randomly select 24 VA facilities stratified by size and racial mix and then select a simple random sample of 156 eligible veterans from each sampled facility. Prior to the national survey, a pilot survey was conducted with the purpose of refining both the study instruments and the study protocol. The sample consisted of 900 randomly selected veterans from the Minneapolis VA Medical Center meeting the same sampling eligibility criteria used for the national mailed survey. The mailed patient questionnaire, made up primarily of previously validated measures, included measures of self-reported CRC screening behavior; patient demographic, health, social network and medical care characteristics; CRC screening knowledge, attitudes, social norms and self-efficacy; and attitudes toward medical care. Additional measures of organizational-level CRC screening practices from a recently completed VA facility survey were linked to the patient survey.The primary outcome is whether the patient is currently compliant with CRC screening guidelines (i.e., received either a fecal occult blood test in the past year, a sigmoidoscopy or double contrast barium enema in the past five years, or a colonoscopy in the past ten years). The primary analyses tested (using logistic regression and a multi-level, structural equation modeling approach) specific hypotheses about the association between this measure and patient background, cognitive and environmental factors and their interactions. Additional analyses conducted include a multinomial logistic regression to assess patient screening mode preferences and their determinants, and logistic and multinomial logistics regression analyses with interactions to determine whether and why any observed patterns in CRC screening behavior vary by race.