Prior communication of organ donation wishes to family increases the likelihood of family consent for donation. However, many people have not shared their wishes. This chapter provides a narrative review of the psychosocial factors used to understand people's decisions to communicate their donation wishes via donor registries/cards and in conversation with family. Traditional (e.g. using demographic characteristics to create donor profiles) and more recent (e.g. using social-cognitive theory to predict communication intentions and behaviour) approaches applied to understand decisions to communicate donation wishes, and their associated limitations, are reviewed. Four key areas where there is scope for consideration are identified: consistency and compatibility in measurement; the assumption that decisions to communicate donation wishes are reasoned and rational, the intention-behaviour relationship, and the potential for other variables not tested to impact on communication decisions. Based on the review, recommendations are proposed that offer a way forward for research to increase communication of organ donation wishes. These include: increased focus on behaviour; further examination of emotional and affective variables; greater attention to family discussion as an extension to the research about joining donor registries; re-examining the conceptualisation of family discussion (conversation vs. notification); and including both individual and family perspectives in efforts to understand communication of donation wishes.