Christopher Whitby

Sandstone Retreat, officially the Sandstone Foundation for Community Systems Research, was established in 1969 on a 15-acre estate in the Santa Monica Mountains, overlooking Malibu. The venture was founded by John and Barbara Williamson, who believed that monogamy was restrictive and that partner exchange could lead to more fulfilling lives. John Williamson, an engineer with a background in missile systems and electronics, purchased the property in 1968. The retreat offered its members and guests, all over 18, spa-like amenities alongside communal sleeping and bathing facilities. Prospective members underwent interviews to assess their suitability for the community's ethos. The resort was managed by a rotating group of up to 20 residents. At its peak in the early 1970s, Sandstone attracted notable figures from various fields, including academics, authors, and celebrities, alongside the general public. The Williamsons sold the resort in 1973, and it ceased operations in 1976, reportedly never achieving profitability. The site's structures were later destroyed in a 2025 wildfire.

The Sandstone Foundation for Community Systems Research was born from the philosophical convictions of John and Barbara Williamson. John, a former engineer involved in aerospace projects and an electronics entrepreneur, acquired the 15-acre property in 1968. Together, the Williamsons envisioned a community that challenged traditional monogamy, which they viewed as sexually limiting. Their alternative model centered on partner exchange and open sexuality, aiming to liberate individuals from perceived societal constraints. The retreat provided a unique environment for its members and guests, offering communal living spaces, including both indoor and outdoor sleeping areas, in addition to shared bathrooms. Access was regulated through interviews, ensuring that individuals seeking entry aligned with the community's foundational beliefs and practices.

Managed by a resident community of up to 20 individuals, Sandstone became a notable gathering place during the early 1970s. Its open atmosphere and philosophical underpinnings attracted a diverse range of individuals. Prominent figures who visited or were associated with the retreat included Daniel Ellsberg, Anthony Russo, Betty Dodson, Max Lerner, and Dr. Alex Comfort. The guest list also comprised numerous Hollywood celebrities, educators, legal professionals, and members of the broader public. Despite its notable clientele and unique social experiment, the resort faced financial challenges, leading to its sale in 1973 and eventual closure in 1976. The legacy of Sandstone was further documented through a 1975 film and mentions in significant publications.