The objective of this article is to develop a mean temperature difference approach to heat exchanger analysis that follows naturally from the underlying classical solution relations. The analysis gives rise to a basic optional defining relation for the number of transfer units NTU(I) that provides the basis for expressing the effective mean temperature difference EMTD directly in terms of NTU(I) and the effectiveness P. The resulting relations give rise to the EMTD method, which represents an alternative mean temperature difference approach that does not involve the traditional correction factor F.