The papers contributed to this Special Issue were inspired by the papers presented at the 2008 IEEE International Symposium on Circuits and Systems (ISCAS) and the 2009 IEEE Sensors conference. In both of these international events, we have initiated special sessions regarding low-power imager arrays and low-power memory arrays. The growing field of "smart sensors" triggered our attention to the fact that it has been a while since such a special Issue was provided on this subject, especially with emphasis on low power. The incentive was the recent results, showing that advanced concepts utilized in one niche implemented for large arrays, can be actually beneficial for the other. Moreover, there are systems on-chip where both kind of arrays are implemented, and leverage can be sought. This gives analog and digital designers another boost for developing creative circuit solutions for low-power array based systems. Also, technology and engineering progress have enabled Active Pixel Sensors (APS) in CMOS to compete with Charge Coupled Devices (CCDs) in imaging quality and to surpass them in focal-plane image processing applications, especially for low-power systems such as the cellphone. All these developments seem to show that the field of low-power sensor and memory arrays will be exciting and growing in the future. The papers in this Special Issue cover a broad range of topics, such as smart sensory arrays, new concepts for memory design, and integrated systems. The papers also come from four different continents. We have gathered the Special Issue papers in three groups. The first is image sensor array papers, the second is newmemory array design papers, and the last is other integrated arrays.