This is an introduction to planning effective missions for Uncrewed Aircraft Systems (UAS) for Water Science Centers. An overview will be presented for establishing capabilities, selecting UASs and sensors, mission planning, data processing, quality assurance and publication for UAS-collected data. Logistical and safety considerations, as well as scientific best practices will be discussed. Examples of UAS projects and use cases from across the Nation will be presented for streamflow monitoring, flood response, terrain mapping, groundwater - surface water exchange zone identification, and more!