Abstract This study evaluated the relationship between perceptions of training results, professional development and organizational citizenship’s behaviours, based on a study at a public university. The research is descriptive and employed quantitative and qualitative approaches. Data were collected in three successive stages: documentary analysis, a survey with alumni (n = 231) and a focal group composed of managers (n = 11). Descriptive statistics, structural equations modelling and content analysis were used for the data analysis. The results showed convergences between the opinions of alumni and managers regards on the impact of training. Tests indicated that the impact of training explains 12% of professional development. For the dimensions of organizational citizenship behavior’s, the impact of training was also statistically significant: creative suggestions (22%), dissemination of the organizational image (10%) and cooperation with colleagues (3%). These findings bring theoretical contributions and practical implications for the training of employees in public organizations.