Corporate volunteering has become a central component of organizations’ corporate social responsibility (CSR) strategy, with more than 90% of corporations currently supporting some form of employee volunteering with nonprofits and charities. However, it is unclear whether such initiatives are strategic from a human capital management perspective, as research to date has been unable to establish a causal effect of such initiatives on important employee outcomes, and we have limited understanding of the mechanisms through which such initiatives might benefit the firm. Implementing a field experiment on a sample of 221 new employees in a large Latin American bank, we find that employees who participated in a corporate volunteering initiative were less likely to leave the company than those randomly assigned to the control group. These employees reported lower levels of work stress; an important employee outcome unexplored in the CSR literature to date. Employees who participated in the initiative also reported higher organizational identification and perceptions about the employer’s social responsibility. Moreover, we show that these CSR perceptions mediate the effect of employee participation in corporate volunteering on employee attitudinal and behavioral outcomes. We advance the literatures on micro-CSR and corporate volunteering by shedding light on the mechanisms through which corporate volunteering can benefit firms and contributing causal evidence of these effects."