Shared decision-making is an increasingly emphasized goal of medicine. While accepted as an aphorism, there are possible negative consequences. The descriptive study by Livaudis et al. explores the consequences of decision making responsibility among women with breast cancer on decision regret; women reporting ‘too much’ responsibility had three-fold greater regret regarding their decision1. Perhaps contributing to this is that women with regret reported insufficient knowledge of treatment benefit. This is similar to findings in another study in which, seven months after surgical intervention, women who preferred more or less decision making responsibility were more regretful.2 It is unclear from either study whether the feelings of regret would change over time. It is troubling that nearly half of women, regardless of desired degree of decision responsibility, reported occasional or frequent problems understanding written information. Many women also reported insufficient knowledge of treatment benefit. With these numbers, it is not surprising that 40 % of the women in the study reported decision regret at 6 months. Clearly, physicians and other providers are far from mastering the shared decision making model and communicating risks and benefits of treatment. The reasons for this are likely multi-factorial including literacy, decision-making preference, lack of good decision aids, inadequate culturally appropriate materials, and failing to check patient understanding. In addition, physicians often feel inadequately trained in incorporating shared decision making into their practice3 and some physicians doubt their patients’ ability to assume a more active role and have concerns about implementing this model within present time constraints.4 As the author’s mention, decision aid tools could help. A recent Cochrane review found that decision aids with explicit values clarification exercises improve informed values based decisions and improved patient-–practitioner communication, with a variable effect on length of consultation.5 Shared decision-making in breast cancer treatment, particularly in patients who desire less decision making and among patients who do not fully understand the treatment, can lead to decision regret. Good decisions require good understanding of treatment options; it is incumbent for providers helping women with these difficult decisions to make sure they fully understand their options.