By the late 1970s, the historical legacy of major land use plans and documents for the Los Angeles region was disappearing at an alarming rate. Documents that comprised the framework of pivotal events in city and regional planning were being lost to an overwhelming lack of storage space and the diminishing archival priorities of local governments.

Concerned planners from local agencies, such as the City of Los Angeles and the County of Los Angeles, and archivists from the Huntington Library, gathered informally in the early 1980s to establish a strategy for preservation and education. From these meetings the Los Angeles Planning History Group (LAPHG) emerged (known as the Los Angeles Regional Planning History Group for decades until the early 2000s when it was renamed the Los Angeles Region Planning History Group and subsequently renamed the Los Angeles Planning History Group in the latter 2010s).

LAPHG incorporated in 1984 as a nonprofit educational organization dedicated to preserving municipal, county and private sector planning documents from throughout Los Angeles County. Thousands of documents have been collected, cataloged and housed at The Huntington Library for easy research access. These documents complement the archives of the California Chapter of the American Planning Association located at California State University, Northridge.

Throughout the 1980s and 1990s LAPHG pursued a collaborative effort with the University of California, Los Angeles to record oral histories of long-established leaders in the planning and development fields to document the pressures, the politics, and the methods used to plan the Los Angeles region. The oral histories of William J. Fox, Milton Breivogel, Simon Eisner, Calvin S. Hamilton, and Edward A. Holden are housed in the planning collection of The Huntington Library and at the UCLA Center for Oral History Research.

The legacy of the founding leaders of LAPHG continue to inspire historical reflections and dialogue about the state of the Los Angeles region and its future. They include Edward Holden, former Director of Planning, Southern California Association of Governments; Calvin S. Hamilton, former Director of Planning, City of Los Angeles; Norman Murdoch, former Director of Regional Planning, County of Los Angeles; Milton Breivogel, former Director of Planning, Los Angeles County Regional Planning Commission; and Alan Jutzi, former Chief Curator of Rare Books at The Huntington Library.