Williamson was previously head of buying, bakery, grocery and wines, at Waitrose and will assume his new post on April 15. He replaces Tony Solomons, who was appointed customer development director in January.
Williamson joined the John Lewis Partnership from Threshers as head of buying, grocery, in June 2004. He started his career in retail at Tesco, before joining Sainsbury's, where he held a number of senior roles, including procurement director and trading director.
JLP chairman Charlie Mayfield said: 'Mark's extensive experience of working with suppliers will be crucial in ensuring that our supply chain continues to support the growth of the business.'
Williamson said: 'We have ambitious plans to expand the Waitrose business and our supply chain strategy will be a critical factor in delivering this.'
Separately, the John Lewis Partnership posted sales up 9.5 per cent for the week to March 31. Sales at Waitrose rose 11.1 per cent for the same week, but results were mixed across its stores. John Lewis department store sales were up 7.2 per cent for the week. The combination of the start of the Easter holidays and fine spring weather led to disappointing trading last Saturday.
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