This paper examines the relationships between variables included in the Norm Activation Model of prosocial behaviour (NAM). Specifically, we evaluate the strength of two commonly used interpretations of this model, namely the NAM as a mediator model and the NAM as a moderator model. Five studies focussing on a variety of prosocial intentions and behaviours provide most support for the NAM as a mediator model. Furthermore, these studies validate past research by showing that variables included in the NAM are powerful in explaining a diversity of prosocial intentions and behaviours in the social as well as in the environmental context