Can we tell our maid of honor and best man what’s not appropriate to say in their toast?

Sure, but let them know in a clear and sensible way. Give them guidelines, such as "Please, no off-color jokes or raunchy anecdotes!" Your concern is totally reasonable (many awkward moments have arisen from wild toasts!). You and your fiancé can have a heart-to-heart with each of them well before the wedding. Appeal to their sense of responsibility (and decency). Sincerely thank them for being in your wedding. Hopefully, each will commit to brief, light toasts, but be prepared for anything. Alcohol, or bad judgment, might creep in. Things happen. Arrange ahead of time for someone -- such as an emcee -- to calmly retrieve the microphone.

World-renowned etiquette expert Peggy Post is a director of The Emily Post Institute and the author of more than twelve books. Post is the author of Emily Post’s Wedding Etiquette.

-- Peggy Post

Learn more about wedding reception toasts:

What makes a great groom's toast?
Who should give a toast at the wedding reception?