This contribution is concerned with interfacial mass transfer into falling films, for which detailed insight is achieved by means of Direct Numerical Simulation employing the Volume-of-Fluid method. As for the numerical model for mass transfer across the fluid interface of falling films, we employ the two-scalar approach. We examine the influence of wave regimes and flow patterns on local Sherwood numbers and identify distinct mass transfer enhancement mechanisms taking effect in specific wave regimes. (C) 2013 Elsevier Ltd. All rights reserved.