An analytical model is presented addressing the effect of lateral conduction due to varying adiabatic wall temperature distributions in transient film cooling experiments using thermochromic, liquid crystals (TLC). Applying the analysis for a typical experimental situation shows, that results evaluated without taking the lateral conduction effect into account can lead to erroneous results especially in the regions of high film cooling effectiveness. An alternative data evaluation procedure is suggested considering the lateral conduction effects based on the given analysis. (c) 2006 Elsevier Ltd. All rights reserved.