Today, ever-increasing pressure on the environment -- the destruction of naturally balanced ecosystems, the plundering of natural resources that once seemed inexhaustible, the extinction of species after species -- has shown the world the fragility of our planet. Our collective goal must be to stabilize the environment, to recognize the dangers we face, and to protect the planet from our less sensitive interventions. The National Parks are both a significant step towards this goal and an unsurpassed historical, educational and natural resource.