Within the context of leadership in education as a differentiating dimension of teacher performance in Portugal, its impact on the level of teacher motivation stands out, which will be the focus of this research project. Self-determination theory proposes a multidimensional conceptualisation of motivation and distinguishes how different types of motivation can be promoted or discouraged. In order to apply it to the educational context, this study aimed to adapt and validate the Multidimensional Work Motivation Scale (MWMS). The scale was answered by 468 teachers in 30 school groups in the north and centre of Portugal. Factor analysis indicated a 19-item scale with a factor structure similar to that obtained in the original studies. This study found that the items that make up the MWMS are good indicators of the constructs they are intended to measure in an educational context and that the factors are properly individualised. The scale showed five robust dimensions common to the original scale studies. The dimension with the best internal consistency is demotivation and introjected regulation is the lowest.