The overall goal of this project is to design, develop, and demonstrate using a flight test, a miniature, high accuracy attitude determination system (ADS) for use on small satellites. Currently available ADS are too large and heavy, or, units for small satellites do not have sensors with sufficient accuracy for important applications such as formation flying or laser-based communication systems. We will overcome these limits by combining two technologies that Creare has previously demonstrated: a 1/2U-sized, high accuracy star tracker; and MEMS inertial measurement unit (IMU). The star tracker relies on unique optics technology that allows the implementation of telescope-quality optics in approximately 1/2U CubeSat and the MEMS IMU has near laser gyro accuracy in a package that is significantly smaller and less expensive than traditional IMUs. During the Phase I feasibility demonstration, we will clearly illustrate the advantages of our approach. Creare and our academic partner, University of Hawaii Spaceflight Laboratory (HSFL), are well qualified to succeed in this effort given our considerable and unique past experience in miniaturizing devices for use in important space missions, our firm's longevity, the space-qualified fabrication facilities that we maintain, and HSFL's unique ground and space testing environments. The proposed program provides an opportunity to accelerate the demonstration of new technology that will greatly enhance the capabilities of small satellites in a spaceflight mission during the Phase II project and within the Phase II budget.