Reevaluation of Colombia's Llanos basin has identified 10 plays and 94 leads and prospects. In the first of a series of review articles on the areas set aside for licensing, new potential is identified in the Llanos basin for both deeper, higher risk, but large Paleozoic targets and for smaller, shallower traps involving proven lower risk plays. Thus Columbia has once again become one of the more attractive exploration venues in the Western Hemisphere.