21 Elements is an award-winning collaborative planning project that helps all the jurisdictions in San Mateo County address their housing needs.

Co-sponsored and coordinated by the San Mateo County Department of Housing (DOH) and the City/County Association of Governments of San Mateo County (C/CAG), 21 Elements has successfully brought together twenty-one unique communities and assisted them as they work to provide a growing and changing population with a variety of housing choices.

Welcome and thank you for visiting our website. Follow these links to learn more about our work.

• New Housing Laws

• Impact Fees and Inclusionary Housing

• Short Term Vacation Rental

• Displacement

• Second Units / Junior Second Units

• 21 Element Meetings/ Webinars