- Sigma Xi - Web Site
- Psi Chi - According to GuideStar (login required) and the official site, a chapter of Psi Chi, the national honor society for psychology, exists, but I can't find anything on Williams sites.
- Phi Beta Kappa - For all you high-GPA people.
- Gargoyle Society - Not, as CC minutes would have you believe, "a group made up of people who have successfully spotted the Gargoyle(s) on the north facade of Morgan."