The purpose of this study was to examine the relationship between causal attributions for the uncontrollable, negative event of breast cancer and coping with the event. A total of 42 women who had undergone mastectomy as treatment for breast cancer were intensively interviewed. Both quantitative and open-ended questions were used to elicit attributions of causality by respondents. Respondents completed four coping measures that assessed depression, emotional state, self-esteem and resumption of pre-mastectomy activities. An attributional model of coping was constructed to examine the hypothesis that causal attributions would be associated with adaptive coping to the extent that they enabled the respondents to feel invulnerable to future cancer. Results showed that coping responses were successfully predicted by perceptions of invulnerability; invulnerability was successfully predicted by perceived success of mastectomy in removing all the cancer and perceived avoidability of a recurrence of cancer. Causal attributions to the controllable factor of behavior were linked to adaptive coping; causal attributions to the non-modifiable factors of other people and personality were linked to poor coping. A sample of 11 husbands of respondents completed questionnaires that included measures of their wives' ability to cope with breast cancer and mastectomy; there was significant agreement between husbands and wives concerning the wives' coping responses. Respondents' answers to "Why me?" and their perceptions of changes in their lives post-mastectomy were also examined.