Patient-centred models of quality cancer care typically encourage engagement of patients in shared decision-making about treatment options. However some patients pose challenges because of indecisiveness, apparent difficulty in making decisions, or even variable adherence to previously-agreed treatment regimens. These behaviours may not be anticipated and can test even the most experienced clinician who finds it difficult to understand why the individual has responded this way. This presentation provides an overview of the complex determinants of personality and adult adjustment, drawing on emerging evidence about the neurobiological correlates of exposure to early life stress. Concepts of loss and grief will also be considered in terms of the ways in which these may shape cognitive and personality styles into adulthood. Case vignettes will be used to illustrate the ways in which past experiences continue to exert an influence on responses when confronted with the challenge of cancer. The cases will include strategies for exploring patient concerns and responding to these challenges.