Abstract Two recent papers have dealt with several methodological and application issues related to the technique of decomposing changes in industrial energy consumption. In this paper, we examine these issues in the context of another commonly adopted approach to decomposition, ie decomposing changes in aggregate energy intensity for industry. The scope of our study includes two general parametric Divisia methods, a unified decomposition framework, five specific decomposition methods and method selection in actual application. We show that decomposition can be done in an infinite number of ways and some previously proposed decomposition methods using the energy intensity approach are special cases of the two general parametric Divisia methods. We also compare the energy intensity approach with the energy consumption approach to decomposition in actual application. Results of application studies using Singapore and Taiwan data are presented to illustrate the issues raised.