He succeeds Tom Bolland, who will become chief strategy officer for the investment banking division in Europe.
Hayes, who takes up his position in January, will be relocating to London from New York, where he is currently global markets controller.
Lehman chief executive officer Jeremy Isaacs said: ‘Kevin brings significant strategic business experience to this role.
‘During his seven years with Lehman Brothers, Kevin has led the evolution of the capital markets finance and control functions and has been instrumental in the development of many of the firm’s financial models.
‘His global expertise will be invaluable to us as we further develop our European and Asian businesses.’
Brian Burke, business development director, has moved within the firm to 'develop Quantuma’s networks with Sussex professional firms'
Stephen Mills joins the Manchester office from IBM, where he spent 12 years as an associate partner in the data, analytics and cognitive consulting group
Rupert Guppy will be responsible for capital allowances in the southern region, and joins the firm from specialist consultancy E3 Consulting
Richard Lewis has been appointed to the firm's restructuring and recovery services team