Up to 1,000 new jobs are to be created in South Yorkshire as online fashion retailer, ASOS, moves its distribution operation to Barnsley.
The move to a 500,000 sq ft warehouse on Park Spring Road in Barnsley is expected to take place in early 2011.
The firm, which operates from Hemel Hempstead, said its existing staff were welcome to transfer to the new site.
Unipart, which runs logistics for ASOS, said it would also try to find other work for staff in Hemel Hempstead.
About 360 full-time staff and varying numbers of temporary workers currently work at ASOS's Hertfordshire warehouse.
The new building in Barnsley will be three times larger than the current warehouse, reflecting the company's continued growth.
Pre-tax profits for the year to March rose to £20.4m from £14.1m a year ago. International sales almost doubled to £63m, while UK sales rose 20% to £160m, the company said.
The firm, which specialises in celebrity-inspired fashion, has 3.7m registered users.
A spokesperson for ASOS said: "Logistics have been critical to our business and the team at the distribution centre at Hemel has been at the centre of our success.
"We have been in Hemel for five years during which time our sales have grown substantially. We now need a considerably larger distribution centre to provide capacity for the future both in the UK and our expansion overseas."
A spokesperson for Unipart said: "In the logistics business contracts regularly move to new sites to accommodate growth and changes in business.
"Unipart has a good track record of responding to these changes and providing the best possible alternatives for employees affected by the change."