He brought his sense of History to Sonoma and Marin Counties in the late 1970's and became an advocate for Historic Buildings
Dan Peterson is a Historical Architect and Planner, a California native , born in 1937 and grew up in Sierra Madre, California. He and his wife, Geraldine, started their preservation practice in 1975 in Santa Rosa. The Firm completed two of the earliest historic resource surveys funded by the Office of Historic Preservation, which resulted in the publication of two books, “Petaluma’s Architectural Heritage”, and “Santa Rosa’s Architectural Heritage. These publications were the foundation of preservation in Sonoma County. He was one of the founding member of the Sonoma County Landmarks Commission. The firms resume of projects in Santa Rosa includes the relocation and restoration of the Old Post Office and Federal Building (now the Sonoma County Museum), the National Register application for Railroad Square, and the restoration of a number of buildings in Railroad Square and Santa Rosa.  He has been the Historic Architectural Consultant for the City of Larkspur's Cultural Heritage Board since 1978 assisting with their inventory and project reviews

A number of the projects have received design awards from California Preservation Foundation, which includes The Old Post Office Restoration, Restoration of South Pasadena Oaklawn Bridge (designed by Greene and Greene Architects), and Historic American Engineering Record (HAER) Documentation of the San Francisco Oakland Bay Bridge. The City of Santa Rosa, the Sonoma County Historical Society, and the American Institute of Architects, Redwood Empire Chapter, have also honored them for their work.