Australian batsman David Hussey will lead Nottinghamshire in the Friends Provident t20.
Regular captain Chris Read, who will continue in charge of the championship and 40-over sides, has agreed to step aside and allow Hussey to skipper in the shortest form.
"Captaining in Twenty20 cricket can be very intense and I feel that it's best for me and the team if I take a break and draw on David Hussey's experience," said Read.
"David has an excellent record in this format and he'll have his own ideas on how the team should approach matches that I'm sure we'll all learn from.
"He'll have my full support and the support of every player in the dressing room."