The present paper describes a quasi-experimental research presenting a workplace training program aimed at helping managers to be more supportive of their employees' autonomy. Drawing on self-determination theory, we built a pre/post questionnaire design measuring perceived autonomy support, need satisfaction, need frustration, autonomous motivation, controlled motivation, work engagement and job burnout. Seven managers were trained according to the autonomy support training program. We assessed 39 of their employees before and after the intervention. Moreover, 133 employees whose managers were not included in the training program constituted the control group. Regarding the experimental group, the results showed significant statistical differences regarding perceived autonomy support from managers, autonomous motivation, need satisfaction, work engagement and job burnout. No significant effects regarding perceived autonomy support from coworkers controlled motivation, or need frustration were observed. This study provides added value to the theory of need satisfaction and demonstrates that training managers to be need-supportive may be effective in improving positive work-related outcomes and reducing negative outcomes.