This study sought to examine the relationships between decisional role (preferred and assumed) at time of surgical treatment (baseline), congruence between assumed role at baseline and preferred role 3 years later (follow-up), and quality of life at follow-up. Two hundred and five women diagnosed with breast cancer completed the decisional role preference scale at baseline and follow-up, and the EORTC QLQ-C30 at follow-up. A statistically significant number of women had decisional role regret, with most of these women preferring greater involvement in treatment planning than was afforded them. Women who indicated at baseline that they were actively involved in choosing their surgical treatment had significantly higher overall quality of life at follow-up than women who indicated passive involvement. These actively involved women had significantly higher physical and social functioning and significantly less fatigue than women who assumed a passive role. Quality of life was significantly related to reports of experienced involvement in treatment decision making, but not to reports of preferred involvement, or congruence between preferred and experienced involvement. Copyright © 2005 John Wiley & Sons, Ltd.