AbstractAsummaryof a technical evaluation of the Decca, Differential Omega and Loran‐C systems' capabilities to fulfill the navigation requirements of mariners in the U. S. Coastal Confluence Region is presented.This paper includes a summary of marine operational requirements, system evaluation criteria and system performance comparisons. The results of the evaluation lead to the recommendation of a system for implementation to satisfy the marine navigation needs in the U. S. Coastal Confluence Region.The work was completed by Polhemus Navigation Sciences, Inc., under contract to the U. S. Coast Guar