We aimed at developing and validating a scale on the beliefs and attitudes of mental health professionals towards services users’ rights in order to provide a valid evaluation instrument for training activities with heterogeneous professional groups. Items were extracted from a review of previous instruments, as well as from several focus groups which have been conducted with different mental health stakeholders. The preliminary scale consisted of 44 items and was administered to 480 mental health professionals. After eliminating non-discriminant and low weighting items, a final scale of 25 items was obtained. Exploratory and confirmatory factor analyses produced a four-factor solution consisting of four dimensions; system criticism/justifying beliefs, freedom/coercion, empowerment/paternalism and tolerance/discrimination. The scale shows high concordance with our theoretical model as well as adequate parameters of explained variance, model fit and internal reliability.