Before establishing Thurstan, James served as the Design Director at Soho House, where he oversaw the design of several members' clubs and hotels for the company.

One notable project under his supervision was the transformation of the former American Embassy into Soho House Istanbul, a sprawling 180,000 sqft space featuring 87 bedrooms, club facilities, a reception area, spa, gym, cinema, and three restaurants. The restoration process involved significant attention to detail and a substantial time commitment to return the property to its former grandeur, carefully preserving its original details.