Abstract
This paper argues that change processes in psychotherapy can be understood more clearly by comparing them with other change-inducing social relationships. In showing how this may be done, different social interactions (e.g. religion, parenting, education, politics, coaching, and sales) are described and discussed in terms of a parsimonious set of common factors in change. The importance of the cross-fertilisation of psychotherapy and other fields is stressed, and research recommendations are offered.