Inspired by Karl Polanyi's assertion that a self-adjusting market cannot persist without undermining the human and natural fabric of society, this book explores the critical role of market regulation in sustaining capitalism. It defends the thesis that "regulation is saving capitalism," while acknowledging the cyclical nature of market regulation: periods of regulation are often followed by waves of deregulation, creating “a swinging pendulum” phenomenon. Combining approaches from political economy and history of regulatory approaches in theory and practice, the book investigates the sensitivity of the pendulum to its driving forces incl. “material causes,” changes in a political power, competing interests, etc. It verifies the capacity of two main theories of regulation to explain this cyclical phenomenon. Part I. of the book examines, with a specific focus on regulation in the European Union, main goals of regulation, the redistributive effects of regulation, regulatory capture by vested interests including “international policing mechanisms,” risks of regulatory failure, the dangers of overregulation, and limits of self-regulation as well as questions the efficacy of the Better Regulation agenda. Part II. provides an in-depth analysis of financial regulation, it explores the key endogenous factors and some exogenous factors of financial instability (like COVID-19, climate change) which underline the need to regulate financial capitalism in order to maintain financial stability without jeopardising innovation, growth and competitiveness. It discusses the rapid evolution of European financial regulation since the 2007/8 financial crisis, including efforts to complete the European Banking Union, advance the European Capital Market, and promote Sustainable finance. Drawing on the author's scholarly as well as practical experiences as the former Deputy Prime Minister (1994) and Finance Minister (1998-2002) of the Slovak Republic, this book is written for both professionals in regulatory agencies and government institutions, as well as scholars with an interest in regulatory issues and economic policy.