The objectives of this study were two-fold. Stage 1 was to describe the clinical and sociodemographic characteristics of patients on the waiting list for coronary artery bypass surgery. Stage 2 was to assess changes in functional status using the SF36 at three intervals over patients’ first year on the waiting list. A cross-sectional study using a postal questionnaire was designed for Stage 1, while Stage 2 was a prospective study using SF36. The setting for the study was two large teaching hospitals in Northern Ireland which receive referrals for coronary angiography. All patients referred for coronary artery bypass over a consecutive six month period formed the study sample. The study consisted of Stage 1: 175 patients at referral for surgery, and Stage 2: 70 randomly selected patients. Results of this study found at Stage 1 that 65% of patients had grade 3–4 angina, 63% of those eligible to work were unemployed due to heart disease and 50% reported a recent decrease in income. Stage 2 found that at referral for surgery patients’ mean functional status was considerably less than 60% of optimum capacity on every dimension of the SF36. Functional status improved between referral and six months, but deteriorated between six months and one year – physical role limitations (10.4–1.8) and social function (52.7–38.1) (p = < 0.05). There was a significant association between functional status and angina grade (p = < 0.05). Waiting for coronary artery bypass surgery was associated with angina, unemployment and reduction in income in this sample. Levels of functional status were low and deteriorated further after waiting longer than six months for surgery.