The disintegration of a water sheet into a spray has been studied with the objective of improving the understanding of the fundamental mechanisms of atomization. Flow visualization, frequency analysis, and LDV are used to identify and characterize the importance of vortex interactions in the atomization process, reflected in the formation of liquid filaments. A three-dimensional vortex dynamics simulation has been developed to model the instability growth in the flow. Preliminary results support the hypothesis that it is the interaction between the vorticity generated by the high-speed air and the vorticity present inside the liquid sheet, generated in the nozzle, which leads to complex disintegration phenomena.