We examine in this work the possible correlations between the rate of water solubilization in inverse microemulsion systems (AOT/n-decane/H2O, with different additives) and the fluidity or rigidity of the droplet amphiphilic film. Conductivity measurements are used to characterize the existence (or absence) of droplet percolation. The stopped-flow technique with turbidity detection has allowed us to perform fast injection of small amounts of water and to follow the kinetics of water uptake. A careful control of the flow rate was found necessary to obtain relevant data. A stirred-cell with variable stirring rates was also used for additional measurements. Different additives known for their effect on the droplet behavior (either favoring or retarding droplet coalescence) were considered in this study : NaCl (0-0.3 M); POEG (with molecular weights 2000 and 10000); n-alkanols (from l-butanol to l-decanol). The turbidity changes with time were best fitted with biexponential functions, where the fast process characterized by a first-order rate constant k(1) (s(-1)) was assumed to control the collisions between the dispersed water droplets and the water-in-oil microemulsion droplets. The significance of this rate constant is analyzed, taking into account the part played by the distance from the phase boundary. The results demonstrate a systematic tendency for hi to be larger for the percolating systems compared to the nonpercolating ones. The possible relation of k(1) with the amphiphilic film rigidity is discussed.