From the perspective of leader-member exchange theory, we investigate how two forms of leadership style (uniform leader-member exchange (ULMX) and differential leader-member exchange (DLMX)) impact member participation in online collaborative work communities (OCWC). Furthermore, based on computer simulations, we also examine the moderating impact of key contextual factors on the relationship between leadership style and member contributions. Efficacy of leadership style in OCWCs is greatly influenced by environmental conditions. DLMX is more effective in sustaining member commitment under high environmental uncertainty, regardless of network size and structure. ULMX is more effective in decentralized structures and during the early stage of community growth. The simulation-based insights suggest that supervisory behavior does matter to member retention and sustained participation in OCWCs, but its impact is significantly moderated by many contextual factors, such as community size, structure, maturity, and environmental uncertainty. In certain situations ULMX prevails, but in others DLMX is more effective. These two forms of governance in fact complement each other, rather than being mutually exclusive forms of leadership style. To attain a maximal outcome, leaders should flexibly adapt their governance styles between DLMX and ULMX over the life cycle of an OCWC to maximize member retention and performance benefits.