Little is known about the effectiveness of workplace coaching from a Civil/Public Sector perspective. This study examined the effectiveness of workplace coaching among 111 Irish Civil Service line managers, of which 69 had received coaching skills training versus 42 line managers that have not, in terms of their intrinsic motivation, extrinsic motivation, job satisfaction and organisational commitment. Furthermore, it examined if organisational commitment was a predictor of those variables. The results from a quantitative cross-sectional design using a mix of one-way ANOVAs and multiple regression showed that organisational commitment was a significant predictor of job satisfaction. However, none of the other four hypotheses were supported. This study is the first of its kind within the Irish Civil Service, and is beneficial to HR practitioners in designing and developing new workplace coaching models in the future.