The objective of this synthesis is to develop information on distribution of wheel loads on highway bridges. Live-load distribution among the various components of a floor system is one of the key elements in determining member size, strength, and serviceability of a bridge. The synthesis includes a summary of the current specification criteria and their background, a brief overview of available research, an evaluation of the current load-distribution practices in both design and rating, as well as alternative methods for load distribution, and identification of all sections affected by and related to the load distribution provisions. Emphasis has been placed on the criteria for the supporting member, although consideration is given to the interaction within decking systems and between the superstructure and the substructure.  The report for this topic can be purchased at https://www.trb.org/news/blurb_detail.asp?id=3446