Apple CEO Tim Cook is about to take over one of the most significant parts of Apple’s business: its design team. The team currently reports to COO Jeff Williams, but once Williams begins his just-announced retirement “late in the year,” the design team “will then transition to reporting directly to Cook,” Apple says.

Apple’s chief operating officer plans to hand the role off this month and retire later this year after roughly a decade as the tech giant’s No. 2 under Chief Executive Tim Cook.

A once leading candidate to replace Tim Cook as Apple’s CEO announced his retirement Tuesday. Chief Operating Officer Jeff Williams, who has worked at Apple for 27 years, will be replaced in a “long-planned succession” by Sabih Khan, senior vice president of operations, who has been with Apple since 1995.