The goals of this study were to ascertain whether a specific leadership behavior (developing subordinates) is related to employees' health complaints and determine some of the underlying mechanisms involved. The hypothesized relationships were investigated in a sample composed of 538 employees working in 170 work-units of a public regional health service. Multilevel structural equation modeling was used to estimate the hypothesized relationships at the individual and work-unit levels. Results obtained at the individual level showed, as expected, that leader developing behavior was negatively related to employees' health complaints through two mediators: organizational commitment and emotional exhaustion. At the work-unit level, leader developing behavior was not related to employees' health complaints. Our findings uncover some of the mechanisms linking leader developing behavior and employees' health complaints at the individual level, show that the observed relationships cannot be generalized across levels, and have implications for the Job Demands-Resources theory.