In this research we studied students´ motivational self-regulation as mediator between motivational beliefs and motivational outcomes. Dutch students in pre-vocational secondary education (N=3602, mean age 14) completed a questionnaire on five motivational strategies (Environmental Control, Interest Enhancement, Self Consequating, Performance Self-talk, Mastery Self-talk); motivational beliefs (value attached to schoolwork, competence); and motivational engagement (pleasure, effort, persistence, achievement). A validation of the self-report questionnaire on the five motivational strategies showed a good fit. Structural equation modelling indicated that strategy-use partly mediates the relation between value, and effort and pleasure. Competence showed a weak direct relation with effort an pleasure. No relations were found for achievement. Further implications of these findings for practical use and further research are discussed.