Psychological difficulties are common after myocardial infarction (MI). These difficulties are most often represented to patients through cardiac rehabilitation services and the literature offered to patients after MI as being related to "stress" and its management. However, no research has examined what MI patients understand by the term "stress" or how congruent lay views of stress are with those evident in the professional literature. The aim of the study reported here was to examine post-MI patients' views of stress, its functioning and relationship to their MI. As patients' views of stress were sought, qualitative interviews were used. A philosophical approach was taken (critical realism) that recognizes the legitimacy of both professional and lay perspectives. Data were generated in 44 semistructured interviews with 14 MI patients who were interviewed 48 hours, 1 week, 1 month and 3 months after hospital admission. While participants described their experiences after MI as being difficult, to convey this they used everyday terms such as fear, fright and worry. Rather than viewing stress as being a consequence of their MI, they perceived it to be a common cause of heart problems. Many considered stress as having a more influential role than other risk factors, such as smoking and diet. They expressed a wide variety of sophisticated and diverse views of stress and its functioning. Each of these views placed different weighting on the roles of social, personal and situational factors in contributing to the stressful reaction. Parallels were apparent between these lay accounts and theories of stress developed in the professional literature.