The purpose of the Anthropometry and Body Composition Working Group (ABCWG) Workshop is to bring investigators together to work toward agreement on a core set of anthropometry-based variables for pediatric obesity projects in all settings. Inconsistency in many study variables has limited systematic reviews and meta-analyses.  A uniform set of widely obtainable variables for estimates of fatness is a basic place to start.  The goal of a core set of variables is to facilitate comparisons across published reports, not to recommend specific study outcomes.