We begin the study of the power to tax in democratic states with a review of six well-known models that have been used to investigate important aspects of the formation or evolution of tax systems. Five of them include collective choice as an integral part. Johansen's challenge to “go further and to consider the public sector in another way” has not gone unanswered in the fiscal literature during the last four decades. Many authors have attempted to explain how selected aspects of tax systems, or tax structure as a whole, emerge in an equilibrium resulting from the interaction of the private economy and the political process. The major contending frameworks include the median voter model, structure-induced equilibrium, probabilistic voting, the Leviathan model, and cooperative game theory. We provide a sketch of each of these approaches.