A Landsat Data Continuity Mission (LDCM) will advance the legacy of the Landsat program with the intesnt of serving science and society. The performance of the Landsat 7 satellite system, the predecessor to the LDMC, has set a standard with respect to rigorous calibration, an enlightened data policy, and global data collection. LDCM requirements advance this standard in accordance with public law, current technology, and Executive Office direction. The LDCM will provide a core capability that serves as a foundation for a global land observing system.