Thresher trading director Alex Anson - best known for his three-for-two initiative - is to leave the post for a new career in Switzerland.
Anson, who has worked for Thresher for almost three years, will be replaced by Gallo UK sales director Lloyd Stephens at the end of January.
Anson has been named new European buying director of Nuance, which
operates 400 airport shops around the world.
Thresher Group chief executive Roger Whiteside described Anson's contribution to the business as "fantastic", adding: "He's been part of the team that's helped to drive changes through the group. I'll be sad to see him go, but it's a big career move for him."
Stephens said: "This is a fantastic opportunity to work with a proactive team and a successful business. There's no doubt that multiple specialists are under extreme pressure as grocers move on to the high street, but I truly believe that a healthy multiple specialist sector is critical for the UK market."
Stephens added that he would take time to understand the challenges facing the business before deciding on a strategy.
"I certainly don't have any preconceptions that I'm going to go in and create massive changes," he said.
Thresher is likely to repeat its discount voucher offer next Christmas, according to chief executive Roger Whiteside.
The voucher, which was widely circulated on the internet, had been a "successful exercise", he said. Its popularity led to a 60 per cent sales boost and an increase in cash profit during the offer period from Nov 30 to Dec 10.
"The odd store sold out of Champagne or high-end French wines, but the vast majority coped extremely well. This is the third time we've done a friends and family offer, but it's never gone quite as mad," Whiteside said.
The vouchers, offering 40 per cent off single bottles of wine and spirits, were
e-mailed to Thresher Group clients and uploaded to the Stormhoek website.
Anson offers sector advice before heading for Swiss role
Anson joined Thresher from Tesco with a reputation for hard-nosed negotiations with suppliers.
"As soon as I joined I was getting slated for bringing in bogofs and beating up suppliers," he said. "But it was the first time we'd seen like-for-like growth in 15 years."
He is proud of the success of three-for-two but admits to "frustration" that it has not yielded more new customers. "In spite of all the investment in advertising - and we spent several million quid above the line in the autumn - it just shows how hard it is to change consumer behaviour if it isn't discount driven," he said.
He predicted that Thresher will "continue to evolve" its retail brands as it competes in the middle ground of drinks retailing. "There will always be off-licences in the market because the consumer needs convenience," he said.
"But the sector is under a lot of pressure and won't necessarily be in the shape it's in now in five years. We'll see an evolution of the strategy we have now - Thresher needs to continue to find the right solutions."