The origins of the “best man” are a bit murky but were thought to originate centuries ago, where the groom would have to steal his bride-to-be away from her disapproving family.
The best man, therefore, was usually the best swordsman who could fight off anyone who wanted to steal the bride back.
That tradition did not survive through to modern times, but the best man is still a mainstay of any modern marriage ceremony. So what exactly are the best man duties that you’ll be expected to perform?
Best Man Duties: Before the Wedding

Introduce the Other Groomsmen to Each Other
Help the Groom Choose a Tux
Organize the Groomsmen’s Fittings
Coordinate Travel and Accommodations
Plan and Give the Bachelor Party
Best Man Duties: Shortly Before, During, and After the Wedding

Attend the Rehearsal Dinner
Sign the Marriage Certificate as a Witness
Help the Groom and Other Groomsmen Get Ready
Be the Emotional Support for the Groom
Stand Next to the Groom During the Ceremony
Hold the Rings Until the Ring Exchange
Help the Maid of Honor Get Everyone Together for Photos
Best Man Duties: During the Wedding Reception

Stand Next to the Bride in the Receiving Line
Play Host During the Reception
Dance with the Maid of Honor during the First Dance
Give the Best Man Speech
Make Sure the Bride and Groom Get Back to Their Room Safely
Being the Best Man is an Honor
If the groom chooses you as the best man, treat it like the honor it is. He has entrusted you with helping him have a night that he’ll remember for the rest of his life. You’ll be able to help make sure that everything goes well and that the newlyweds start their new married life on a happy note.