On the occasion of its 50th anniversary, we survey the wide range of activities conducted by Acterra, a Palo Alto nonprofit that brings people together to create local solutions for a healthy planet. In the face of daunting environmental challenges, their science-based approach instills hope while building community. The name Acterra stands for "Action for the Planet"--we see some of the many ways that action is taking place. (Produced by Rick Bacigalupi)