Lake Forest is a master-planned city in southern Orange County, California, located inland from the Pacific coast and adjacent to Irvine, Mission Viejo, and Laguna Hills. It is widely known as a primarily residential community with strong links to the broader economic life of Orange County, including technology, healthcare, education, retail, and professional services. Its location near Interstate 5 and State Route 241 places it within the larger Los Angeles–Orange County–Inland Empire urban region.
The city grew from ranch land and planned suburban development, especially in the second half of the 20th century. For many people in Southern California, Lake Forest is recognizable for its neighborhoods of single-family homes, parks, sports facilities, and business areas, as well as for the eucalyptus groves and the two man-made lakes that helped shape the community's identity. Until 2000, the city was officially named El Toro, reflecting the historic Spanish land-grant era and the nearby former Marine Corps Air Station El Toro.
Today, Lake Forest matters as both a place to live and a place to work. It combines suburban housing with industrial and office districts, and it has become increasingly diverse over time. Community life is centered around schools, youth sports, local parks, shopping centers, and civic events. While it is not one of California's largest cities, it is a representative example of Orange County's postwar suburban transformation and continuing regional growth.