The document summarizes the proceedings of a workshop organized by the Energy Sciences Network (ESnet) and the Office of High Energy Physics (HEP) to characterize the networking requirements of HEP science programs over the next 10 years. Key points discussed include: - The HEP community has large, distributed data needs that will continue growing with projects like the LHC. More LHC Tier-3 sites and Tier-2 to Tier-2 traffic are anticipated. - The two LHC Tier-1 sites in the US predict needing 40-50Gbps capacity in 2-5 years and 100-200Gbps in 5-10 years to support HEP traffic. - There are