This collection of essays honouring Dan Felsenthal and Moshé Machover reconsiders foundational aspects of the measurement of voting power. The specific case of voting power in two-tier systems - for instance the US system and the EU system - is analysed. Furthermore major power indices - Penrose, Banzhaf, Shapley-Shubik and others - are revisited. The book proposes new voting procedures and studies well-known procedures and/or apportionment methods either from a technical or historical point of view.