While traditional economic literature often sees nominal variables as irrelevant for the real economy, there is a vast body of analytical and empirical economic work that recognizes that, to the extent they exert a critical influence on the macroeconomic environment through a multiplicity of channels, exchange rate policies (ERP) have important consequences for development. ERP influences economic development in various ways: through its incidence on real variables such as investment and growth (and growth volatility) and on nominal aspects such relative prices or financial depth that, in turn, affect output growth or income distribution, among other development goals. Additionally, ERP, through the expected distribution of the real exchange rate indirectly, influences dimensions such as trade or financial fragility and explains, at least partially, the adoption of the euro—an extreme case of a fixed exchange rate arrangement—or the preference for floating exchange rates in the absence of financial dollarization. Importantly, exchange rate pegs have been (and, in many countries, still are) widely used as a nominal anchor to contain inflation in economies where nominal volatility induces agents to use the exchange rate as an implicit unit of account. All of these channels have been reflected to varying degrees in the choice of exchange rate regimes in recent history. The empirical literature on the consequences of ERP has been plagued by definitional and measurement problems. Whereas few economists would contest the textbook definition of canonical exchange rate regimes (fixed regimes involve a commitment to keep the nominal exchange rate at a given level; floating regimes imply no market intervention by the monetary authorities), reality is more nuanced: Pure floats are hard to find, and the empirical distinction between alternative flexible regimes is not always clear. Moreover, there are many different degrees of exchange rate commitments as well as many alternative anchors, sometimes undisclosed. Finally, it is not unusual that a country that officially declares to peg its currency realigns its parity if it finds the constraints on monetary policy or economic activity too taxing. By the same token, a country that commits to a float may choose to intervene in the foreign exchange market to dampen exchange rate fluctuations. The regime of choice depends critically on the situation of each country at a given point in time as much as on the evolution of the global environment. Because both the ERP debate and real-life choices incorporate national and time-specific aspects that tend to evolve over time, so does the changing focus of the debate. In the post-World War II years, under the Bretton Woods agreement, most countries pegged their currencies to the U.S. dollar, which in turn was kept convertible to gold. In the post-Bretton Woods years, after August 1971 when the United States abandoned unilaterally the convertibility of the dollar, thus bringing the Bretton Woods system to an end, the individual choices of ERP were intimately related to the global and local historical contexts, according to whether policy prioritized the use of the exchange rate as a nominal anchor (in favor of pegged or superfixed exchange rates, with dollarization or the launch of the euro as two extreme examples), as a tool to enhance price competitiveness (as in export-oriented developing countries like China in the 2000s) or as a countercyclical buffer (in favor of floating regimes with limited intervention, the prevalent view in the developed world). Similarly, the declining degree of financial dollarization, combined with the improved quality of monetary institutions, explain the growing popularity of inflation targeting with floating exchange rates in emerging economies. Finally, a prudential leaning-against-the-wind intervention to counter mean reverting global financial cycles and exchange rate swings motivates a more active—and increasingly mainstream—ERP in the late 2000s. The fact that most medium and large developing economies (and virtually all industrial ones) revealed in the 2000s a preference for exchange rate flexibility simply reflects this evolution. Is the combination of inflation targeting (IT) and countercyclical exchange rate intervention a new paradigm? It is still too early to judge. On the one hand, pegs still represent more than half of the IMF reporting countries—particularly, small ones—indicating that exchange rate anchors are still favored by small open economies that give priority to the trade dividend of stable exchange rates and find the conduct of an autonomous monetary policy too costly, due to lack of human capital, scale, or an important non-tradable sector. On the other hand, the work and the empirical evidence on the subject, particularly after the recession of 2008–2009, highlight a number of developments in the way advanced and emerging economies think of the impossible trinity that, in a context of deepening financial integration, casts doubt on the IT paradigm, places the dilemma between nominal and real stability back on the forefront, and postulates an IT 2.0, which includes selective exchange rate interventions as a workable compromise. At any rate, the exchange rate debate is still alive and open.