During the past 50 years, a wave of liberalization seized mature democratic and capitalist nations. Liberalization denotes the removal of market barriers and restrictions on free markets. Its opposite—de-liberalization—constrains markets. This contribution aims to answer two questions: (a) What does liberalization mean exactly in operational terms, and how did it evolve in modern developed market economies? (b) Is liberalization only driven by market logics and technological developments, leaving no room for democratic politics, or can the pressure for liberalization be modified in the democratic process? The chapter finds these answers: (a) Focusing on the established democracies since the early 1970s, various data sources indicate that these countries were all exposed to a wave of liberalization that began in the 1970s, peaked around the turn of the century and did not abate significantly thereafter. Reform activity declined, probably because government intervention was significantly reduced by the early 2000s as a result of previous liberalization policies. (b) Democratic politics plays a role in the liberalization phase. However, the effects of democratic competition and discourse are severely limited and far less consequential than politicians’ claims to be able to shape society and the economy in far-reaching ways. Hence, the impact of democratic politics is far from the ideal type of democracy, but on the other hand, democratic government is not completely toothless when demands for liberalization increase.