- Science Tech And CodingOWASP Bay Area ChapterBay Area chapter of OWASP for application-security professionals, talks, and community events.
- Sports Wellness And RecreationOyster Bay Disc Golf ClubOyster Bay Disc Golf Club was incorporated as a non-profit public benefit corporation to support and maintain the Oyster Bay Disc Golf community
- Outdoors And AdventureOyster Point DragonsA 501(c)(3) all-volunteer dragon boat team founded in 2012 and based at Oyster Point Marina; mission is to promote dragon boating in a fun and safe environment while fostering team spirit and friendship; includes adult, middle school (Tiger Sharks) and high school teams.
- Sports Wellness And RecreationPacific Fencing ClubEstablished in 1984, Pacific Fencing Club is one of the oldest fencing clubs in the Bay Area.
- Games And TabletopPacific Mahjong LeagueCompetitive riichi mahjong league using modern Japanese riichi rules with a published rulebook, welcoming both seasoned competitive players and curious beginners.
- Sports Wellness And RecreationPacific Masters SwimmingRegional Masters swimming network for adult swimmers with clubs, workouts, meets, clinics, and social functions.
- Games And TabletopPacific Pinball LeagueBay Area pinball league/community for competitive and social pinball play.
- Arts And CraftsPacific ScribesCalligraphy society for those who love the making of letters in every form, offering classes, workshops, and exhibits; 2022 marked its 40th anniversary.
- Science Tech And CodingPalo Alto Amateur Radio AssociationAmateur radio club serving the Peninsula with meetings, activities, and ham-radio community.
- Games And TabletopPalo Alto BridgeBridge club serving Palo Alto/Peninsula players with games, lessons, and duplicate bridge community.
- Arts And CraftsPalo Alto Camera ClubFounded in 1935 and co-sponsored by the City of Palo Alto Division of Arts and Sciences, the Palo Alto Camera Club serves amateur through professional photographers interested in working together to enhance and broaden their photographic skills and artistic vision.
- Music Dance And PerformancePalo Alto PhilharmonicCommunity orchestra led by Music Director Lara Webber presenting a nine-concert season including orchestra, chamber, and family concerts, mainly at Cubberley Theatre in Palo Alto.
- Science Tech And CodingPapers We Love San FranciscoComputer science paper reading and discussion community; San Francisco chapter of Papers We Love.
- Social And MeetupsParents Helping ParentsBay Area parent-support organization for families of children and adults with disabilities.
- Science Tech And CodingPeninsula Astronomical SocietyThe Peninsula Astronomical Society (PAS) is an SF Bay Area astronomy club of enthusiasts of all ages, backgrounds, and experience. It hosts astronomy talks and runs the public Friday night and Saturday morning observing programs at Foothill Observatory.
- Outdoors And AdventurePeninsula Fly FishersA fly fishing club for the San Francisco Peninsula offering meetings, fishouts, fly tying, skills development, monthly guest speakers, conservation initiatives and social events for all ages.
- Arts And CraftsPeninsula Quilters GuildQuilt guild on the San Francisco Peninsula meeting monthly at the San Mateo Garden Center, with workshops, community outreach, and challenges. Mailing address P.O. Box 2423, Redwood City, CA 94064.
- Outdoors And AdventurePeninsula Velo RacingPeninsula cycling and racing club with group rides and racing history.
- Outdoors And AdventurePetaluma Cycling ClubPCC creates opportunities for cyclists of all levels to meet, make friends, ride and explore together in a safe and supportive environment.' Formerly Petaluma Wheelmen Cycling Club; a 501(c)(7) cycling since 1895.
- Books And WritingPetaluma's Wednesday Book ClubBook club hosted by Copperfield's Books in Petaluma. Meets: Third Wednesday of every month, 10:30am.
- Social And MeetupsPhysics With FriendsA group to explore the intersections of science, physics, and spirituality.
- Culture And LanguagePiedmont Asian American ClubSince 1987, The Piedmont Asian American Club (PAAC) has supported cultural, educational, and social activities in our community.
- Volunteering And CausesPiedmont Beautification FoundationPiedmont Beautification Foundation (PBF) has worked since 1964 to create beautiful public spaces in the City of Piedmont, CA.
- Volunteering And CausesPiedmont Civic AssociationThe Piedmont Civic Association is a volunteer organization dedicated to providing community news on local civic topics.
- Volunteering And CausesPiedmont ConnectPiedmont Connect is a collaborative community organization supporting resident initiatives and city efforts to build a sustainable future.