The LT Method 1.0 was developed for the European Architectural Ideas Competition "Working in the City" as part of the ARCHISOL programme coordinated by the Energy Research Group(ERG), University College Dublin, and funded by the Commission of the European Communities(CEC). This competition focused attention on energy conservation and passive design in non-domestic buildings and in particular on the design of daylighting. A revised version 2.0 was later developed. Version 3.0 is the one discussed herein.

The LT Method was devised and written by Nick Baker, with important contributions from David Hoch and Koen Steemers, at the Martin Centre for Architectural and Urban Studies, University of Cambridge, and Cambridge architectural Research Ltd. Graphics and design by Michael Baker.