This longitudinal study examined the multidimensionality of motivation to transfer training. Based on self-determination theory, expectancy theory, and the theory of planned behaviour, motivation to transfer was conceptualized in three dimensions: autonomous motivation to transfer, controlled motivation to transfer, and intention to transfer. Relationships of these dimensions with attitudes toward training content, knowledge test performance, and self- and supervisory-assessed transfer were investigated to understand further the mediating role of intentions in the transfer process. Participants were 128 trainees in occupational health and safety programs. Confirmatory factor analysis indicated good fit of the proposed three-factor structure. Partial least squares (PLS) based path modelling indicated partial support of the hypothesized relationships. Knowledge gain following training was large (Cohen’s d = 1.00), while attitude change was small (Cohen’s d = 0.27). The findings are discussed in terms of their significance for the development of theories of training effectiveness and their implications for evaluating professional development.