Bernard Zimmerman, FAIA, wore many hats in the Southern California architectural community. He was an architect, planner, educator, preservationist, mentor, and curator. But friends and colleagues say he will be best remembered as the conscience of his profession, a passionate advocate for architecture and design who wasn’t shy about voicing opinions about what he loved and what he loathed.

Zimmerman died June 4 at his Los Angeles home after a long illness. He was 79.

“He was utterly convinced of the rightness of a stringent brand of Modernism—its social as well as its formal principles—and didn’t hold back from chastising any designer he felt had fallen short of its ideals,” says Frances Anderton, host of DnA: Design and Architecture, a monthly program on Santa Monica public radio station KCRW.

Zimmerman helped found the architecture department at California State Polytechnic University, in Pomona, and he taught there for more than 30 years. In 2001, he co-founded the Los Angeles Institute of Architecture and Design, and he helped launch the Architecture + Design Museum. As a curator, he organized a number of exhibitions on the work of Los Angeles architects and designers, including “New Blood 101” at the Pacific Design Center. In 1991, he founded the annual Masters of Architecture lecture series at the Los Angeles County Museum of Art.

He was president of Zimmerman Architects & Planners. He had previously been associated with Richard Neutra Architects, Welton Beckett & Associates, Victor Gruen Associates, and several other Los Angeles firms. As a preservationist, he was involved in efforts to save a number of threatened Los Angeles landmarks, including the Hollywood Sign, John Marshall High School, the Schindler House, Watts Towers, and Angels Flight Railway.

In 1999, he was honored with a Lifetime Achievement Award from the Los Angeles chapter of the American Institute of Architects.

Architect Joe Addo recalls his friend and colleague as an “activist architect” who believed the purpose of architecture was to change the world. He was contemptuous of architects whose work didn’t live up to his ideals. “We used to have lunch together every day, and then we’d drive around looking at buildings, mostly new houses. And if he saw a bad one under construction, he’d go up to the contractor and say, ‘This is a terrible building!’” Zimmerman even joked about handing out soccer-style red cards as penalties for especially egregious examples.

“Bernard always went to the heart of the matter,” Addo says. “He’d ask, Why does this building look the way it does? What is it doing for society?” Architect Ray Kappe, FAIA, a longtime friend, adds: “He was always in everybody’s face. But his main cause was good design.”