This document summarizes the goals and services provided by the Science Gateways Community Institute (SGCI). The SGCI aims to help the science gateway community build gateways more effectively through providing on-demand expertise, extended developer support, a scientific software collaborative, community engagement opportunities, and workforce development programs. Key services include incubation expertise across the gateway lifecycle, hands-on technical support for existing gateways, a platform to share and discover gateway software, and connections for knowledge sharing and professional development. The overarching goal is to support gateway developers and foster collaboration across the science gateway community.