Wide-area sensor infrastructures, remote sensors, RFIDs, and wireless sensor networks yield massive volumes of disparate, dynamic, and geographically distributed data. The Sensor-KDD 2009 workshop solicits papers that describe innovative solutions in offline data mining and/or real-time analysis of sensor or streaming data. Position papers that describe the challenges and requirements for sensor data based knowledge discovery in high-priority application domains, as well as relevant case studies, are particularly encouraged.