Waiting lists for coronary artery bypass surgery (CABS) are common in many developed countries. Yet, there is limited information available regarding patients' health care needs at this time. This paper reports on a prospective study which aimed to investigate the experience of waiting for CABS from a qualitative perspective. An inductive research approach was used to conduct interviews with 70 randomly selected patients at three intervals over the first year on the waiting list - referral for surgery, again after waiting 6 months (n=49), and finally after waiting for 1 year (n=28). Attrition was mainly caused by surgery having been performed (n=36), although death (n=4) and refusal to participate (n=2) also contributed. Domicilliary interviews were taped and transcribed verbatim. Thematic content analysis identified three central themes in this experience - uncertainty, chest pain and anxiety; with six secondary themes - powerless, dissatisfaction with treatment, anger/frustration, physical incapacity, reduced self-esteem, and altered family and social relationships. The nature and meaning inherent in each theme is described using interview quotations, and a model is proposed which summarizes this data and the relationship between themes. From this analysis, uncertainty, chest pain and anxiety emerge as important indicators of a negative outcome for these patients. This report strongly suggests that patients awaiting bypass surgery require more information regarding the waiting time for such a surgery. Nurses should also offer advice regarding pain management to help improve patients' skills and decrease the fear associated with angina. Nursing intervention and support should also be directed at reducing patients' anxiety levels. This is the first known qualitative study which specifically examines patients' perception of the waiting period prior to bypass surgery. It may therefore provide new evidence on which to base practice for nurses in both hospital and community, and may also stimulate further research in this area.