Hall will be working with former Burton managing director Wes Taylor, who was appointed menswear director in March last year.
She joins the retailer following three years at Burton as head of design, and has previously spent six years at Ben Sherman.
A statement from the retailer has said: “As part of our clothing and home business transformation we’re committed to recruiting new talent to help us to re-establish authority in year-round wardrobe essentials by improving fit and style.
“Our designers are critical to this and Karen will bring years of design expertise, as well as a new energy, to our menswear team. We’d like to thank James for his service, and we wish him all the best with his next role.”
The appointment follows the departure of clothing and home chief Jill McDonald in July, with group CEO Steve Rowe assuming the responsibilities in the interim.