The demand continues to grow for small, compact imaging sensors, which include new capabilities, such as response in multiple spectral bands, increased sensitivity, wide high dynamic range, and operating at room temperature. These goals are dependant upon novel concepts in sensor technology, especially advanced electronic processing integrated with the sensor. On-focal plane processing is especially important to realize the full potential of the sensor. Since the area available for focal plane processing is extremely limited, a new paradigm in sensor electronic read-out technology is necessary to bridge the gap between multi-functional, high performance detector arrays and the off-focal plane processing. The Vertically Integrated Sensor Array (VISA) Program addresses this need through development of pixel-to-pixel interconnected silicon processors at the detector, thus expanding the area available for signal and image processing. The VISA Program addresses not only the array interconnection technology, but also investigates circuit development adapted to this new three-dimensional focal plane architecture. This paper reviews progress in the first phase of the program and outlines direction for demonstrations of vertically integrated sensor arrays.