To systematically document key characteristics and features of American Job Centers (AJCs), Mathematica and its partners—Social Policy Research Associates, The George Washington University, and Capital Research Corporation—conducted the Institutional Analysis of AJCs for the U.S. Department of Labor. This paper describes how 40 comprehensive American Job Centers (AJCs) shared resources to help support AJC infrastructure and services. It provides a review of  resource sharing requirements under the Workforce Investment Act (WIA) and the Workforce Innovation and Opportunity Act (WIOA), and describes the extent to which the study AJCs shared resources. For AJCs that entered into formal resource sharing agreements, the paper analyzes resource sharing practices, including funding sources, participating partners, and the use of different cost allocation methodologies. It concludes with implications of WIOA resource sharing requirements for local implementation.