Since their creation in Europe in the seventeenth century, pension funds have grown to become one of the main sources of capital in the world. A number of role players ultimately manage the pension money of members on their behalf. Accordingly, the focus of this study is on the role players involved in the actual investment of pension fund money. For the purposes of the study, the key role players in the pension fund investment chain are identified as pension fund trustees, asset managers and asset consultants. These role players have a specific responsibility in terms of the service that they ought to provide. One of the key aspects of this dissertation is therefore determining whether their responsibility is a fiduciary responsibility. The main purpose of the study is, however, to answer one overarching research question: Does fiduciary responsibility create barriers to the implementation of responsible investment in the South African pension fund investment chain? Clearly, there are two key terms in this research question, fiduciary responsibility and responsible investment. It is suggested that responsible investment takes at least two forms: a “business case” form1 in which environmental, social and governance (ESG) issues are considered only in so far as they are financially material; and a social form in which ESG issues are considered over maximising risk adjusted financial returns. Three key questions were asked in order to find qualitative descriptions and interpretations of fiduciary responsibility: Question 1: Are the key role players in the pension fund investment chain fiduciaries? Question 2: If so, to whom do the key role players owe their fiduciary duty? Question 3: What are the fiduciary duties of the key role players in the pension fund investment chain? It is also suggested that the duty to act in the best interests of beneficiaries could be described as the all-encompassing fiduciary duty. Two main interpretations of the / Private Law / LL.M.