Notions of action research and of integrating object relations and field psychologies have exerted a steady influence on both the initial formation of The Tavistock Institute in London and on the subsequent 60 years of its professional identity and approach to work. These notions can be tied directly to early scientific contact with Kurt Lewin, and indirectly through the Lewinian philosophy that staff incorporated into an overall "house style". From 1990, however, changes in the Institute's funding environment undermined this historical source of integrity. Recent developments to reclaim and update the roots of Kurt Lewin at The Tavistock Institute.