We review in the present work the local-scaling transformation version of density functional theory both for ground and excited states. The historical development of the concept of space-coordinate density-transformation and of its effect on the formulation of several versions of density functional theory is discussed. We then present the various steps in the elaboration of the local-transformation version and indicate some of its accomplishments with respect to the N-representability problem for the energy functionals. Examples are given showing how the application of these methods to atomic sample systems lead to Hartree-Fock energies that are undistinguishable from the SCF values. In addition, the explicit construction of analytic density functionals for the energy, via local-scaling transformations, is discussed and is exemplified for the particular case of the Hartree-Fock approximation for atoms. Finally, applications of local-scaling transformations to the direct solution of the Kohn-Sham equations are reviewed.