This paper presents a wearable system for long-term monitoring of knee kinematics in the home and community settings. The system consists of a knee sleeve with embedded sensors to track knee flexion/extension movements and to monitor compliance with the use of the knee sleeve. Knee flexion/extension movement data is captured using a potentiometer. Compliance with the use of the knee sleeve is monitored by using an e-textile sensor that measures the knee-sleeve fabric stretch thus allowing one to infer whether the subject wears the knee sleeve. The system is also equipped with a wireless unit that has the capability of relaying data to a smart phone. The smart phone can be used as a gateway to provide remote access to the data. Comparison of measures gathered using the proposed wearable system and a stereo-photogrammetric system for biomechanical data collection demonstrates the reliability of the knee kinematic data collected using the proposed knee sleeve.