Open Government Data (OGD) has become a topic of prominence during the last decade. However, most governments have not realised the desired outcomes from OGD, which implies that the envisaged value streams have not been realised. In order to help address this shortcoming, this study aims at identifying the candidate causal mechanisms that are impacting on OGD initiatives. This will be achieved through the lens of critical realism. This will assist implementers of OGD to formulate policies and structures that will help ensure that the initiative is sustainable and capable of achieving the set objectives and goals. Given the inadequacy of current literature on causal mechanisms that impact on OGD initiatives, it will also contribute to the existing OGD literature, mainly through the case studies and the causal mechanisms that will emerge.