To complement legislative measures protecting cetaceans and other marine animals, the Peruvian Centre for Cetacean Research in the period 1993-2000 implemented an environmental education program at the kindergartens, primary and high schools of several fishing towns and in Lima, Peru. This program included environmental classes based on selected thematic videos and educational booklets, creative "marine" workshops, art competitions, guided visits to the Museo de Delfines' in Pucusana and other public events. Approximately 1,920 and 2,135 pupils attended at least one environmental class in 1998 and 1999, respectively. Between September 1997 and February 2000, nearly 1,700 children visited the museum. Five hundred and twenty-three children from Pucusana and Cerro Azul participated in workshops in 1998. In 1999, this number increased to 579 for Pucusana alone. In May 2001, personal interviews were conducted with 55 children in the sixth grade of a primary school in Pucusana to evaluate their knowledge on the conservation themes tackled during the classes. A mean of 77% (min. 40%- max. 98%) of the pupils answered correctly 16 questions on the basic biology of aquatic animals and their environment. The material displayed in the museum was well to very well remembered by 87.3% of the children. Forty-nine (89.1%) of those pupils thought that it is necessary to protect aquatic animals and 54 of them (98.2%) wished to receive more environmental classes and to visit the museum again. Children and adolescents from Pucusana and Cerro Azul, the villages where the program has run for the longest period, displayed an increasing interest, knowledge, and awareness for cetaceans and other protected marine species. The same tendency was noted in the more recently visited fishing towns of Chancay and Chimbote. We believe that our environmental education program is efficiently complementing existing legislation protecting cetaceans, sea turtles, penguins, sea lions, and other marined wildlife in Peruvian waters. (Contains 5 figures.)