A home on Belvedere Lagoon lives differently than one in the Sonoma hills. The light is different. The relationship to water, to sky, to the people inside — all different. At OSA, we design for exactly where a building stands: luxury residences across Southern Marin and Sea Cliff that frame the bay, negotiate the hillside, and endure California’s coastal conditions with grace; and wineries in wine country where architecture shapes how a guest first understands the land, the varietal, the story.

Award-winning practice. Licensed in California.
Active in Belvedere · Tiburon · Mill Valley · Sea Cliff · Sonoma · Napa