The defender will take over the captains armband from Neil Cox from the beginning of the new Coca Cola League One season which begins on August 7th.
“You know what type of character Sean is by the way he plays – always giving his all,’’ manager Ray Lewington told the clubs official website.
“He’s got strong opinions, you always see him talking and he’s a natural leader so there was no hesitation in making him captain.
"He was delighted to accept and I’m sure he’ll make a good job of it.’’