This book presents an analysis of the acoustic coupling between the elements of a MEMS (Micro-Electro-Mechanical Systems) array. Towards this end, the physical model of such an array and its electro-mechano-acoustical circuit has been defined and analyzed. Since the MEMS transducers are combined in array configurations having small inter-element distance, the total pressure field is the superposition of the fields generated by the individual array elements. Such MEMS arrays are appealing because they can be used as digital transducers. The functionality of a MEMS array as a digital transducer is demonstrated and the method of Matched Asymptotic Expansions (MAE) is used. The method is not restricted to a specific geometry or velocity distribution with reference to the surface of the vibrating surface.