variable since the beginning of the project in 1976, up to its actual operation, has played an important roil in the successful management of the watershed of La Fortuna Hydroelectric Project in Panama. An historical resume is given as to how the environmental variable was incorporated early in the project since the seventies when the environmental consideration were at an incipient stage in Panania. The environmental assessment for La Fortuna Hydroelectrie Project was the first environmental evaluation for a development project in Panama. There were not detailed terms of reference for the evaluation as requested today, however, the results and the recommendation generated by the study were like an environmental management plan when no such instrument was used. Recommendations included watershed preservation, environmental regulations, creation of forestry inspectors, watershed management section, natural forest regeneration, population relocation program, occupational health, and special black flies studies. The article succinctly telis about the environmental management since 1976 to 2004.