Glynn, who has been senior partner since 2003, will remain active on client relationships while leading office operations.
With 16 years of consulting experience for clients worldwide, Glynn specialises in brand strategy, customer experience, strategy and organisation.
Prior to joining Lippincott, Glynn was vice-president at Mercer Management consulting.
His clients have included American Express, AOL, Aviva, The Climate Group, MTV Networks, Orange, QVC and Virgin Atlantic.
Ken Roberts, Lippincott chairman and CEO, said: "Our London office has experienced significant growth in recent years and Simon has demonstrated invaluable leadership during this period. We look forward to his continued success in his expanded role with the firm."
Glynn said: "Our clients value the way we blend our unique mix of skills in strategy design and execution, and deliver expertise from across our worldwide offices."
If you have an opinion on this or any other issue raised on Brand Republic, join the debate in the .