Project Summary/Abstract The National Center for CryoEM Access and Training (NCCAT), based at the New York Structural Biology Center, provides access to state-of-the-art equipment, including specimen preparation robots, high-end microscopes and direct detectors, screening microscopes, and all the other ancillary equipment required to solve structures to the highest possible resolution using cryo electron microscopy (cryoEM) methods. A highly qualified technical team provides direct support, guidance and assistance to ensure that structures of the highest quality are produced in the shortest possible time. A cross-training program provides training to users across a wide variety of skill levels and career goals. This is a request for supplemental funding to support a grid preparation and screening (GPS) service for cryo- TEM at NCCAT. The objective is to provide urgently needed support to groups who have limited experience with the methods of cryoEM and limited access to local facilities. The goal will be to support these groups to get them started while also training them in all possible aspects so that they can make best possible use of every resource available to them as soon as possible.