This study adopts the diffusion of innovations model as a research framework to examine adult learner perceptions related to workplace e-learning effectiveness. Recent training reform efforts focusing on e-learning in Taiwan provide an opportunity to explore e-learning effectiveness using questionnaires. The results show that the perceptions and attitudes of adult learners toward workplace e-learning are positive, and relevant factors that affect learner-perceived effectiveness and e-learning expected values are identified. The implications of analyzing e-learning innovation in public sector training and the recommendations for future e-learning research for staff development initiatives are addressed.