This study investigates the effect of training and development (T&D) on firm innovation. Given the inconsistent findings on the performance implications of T&D and the lack of studies on the T&D-innovation relationship, we elaborate the multiple dimensions of T&D, intermediate employee outcomes, and boundary conditions to elucidate the pathways of T&D toward firm innovation. We specifically identify two distinct T&D dimensions, namely, firm investment and employees' positive perceptions. The former and the latter, respectively, reflect top-down and bottom-up approaches. We suggest that these two dimensions indirectly affect firm innovative performance by enhancing employees' competence and commitment. We further hypothesize that T&D-related contingencies (i.e., employees' voluntary participation and T&D evaluation) moderate the indirect effects of T&D on firm innovative performance. We examine the current framework by using multisource data collected at three time points over a 5-year period from 325 Korean organizations. Our analysis confirms that the positive indirect effect of T&D on firm innovative performance through employees' competence and commitment becomes stronger (a) when employees voluntarily participate in T&D and (b) when firms do not implement T&D evaluation. This study provides useful and valid theoretical explanations and practical insights into the design and implementation of T&D in firms. K E Y W O R D S commitment, employee participation, human capital, innovation, training and development Hum Resour Manage. 2018;57:1339-1353. wileyonlinelibrary.com/journal/hrm . Her research interests include knowledge management in teams and organizations, organizational demography, and innovative performance at multiple levels of analysis. JIN NAM CHOI is Professor of Management at Seoul National University, South Korea. He earned his PhD in Organizational Psychology from the University of Michigan. His research interests include innovation implementation, organizational creativity, and multilevel processes of human behavior in organizations. How to cite this article: Sung SY, Choi JN. Effects of training and development on employee outcomes and firm innovative performance: Moderating roles of voluntary participation and evaluation.