Liberalism is one of the major political theories and ideologies of our time, yet it is subject to many and varied interpretations, as well as misunderstandings, which significantly complicate its definition. What does liberalism mean? Greater individual freedom or treating everyone with the same respect? To be more humane or more productive? Is a free but uncontrolled market liberal? Is a democratically elected government that is not accountable for its decisions liberal? Liberal credentials are highly controversial: those who believe that liberalism is mostly about unrestricted private activity, and those who believe that liberalism is about the satisfactory development of the individual within a society of mutual support and collective goals, do not have much in common.

Michael Freeden, one of the most important contemporary theorists of ideologies, analyzes the complex and often misused concept of liberalism by combining historical and synchronic perspectives in this dense introduction. He proposes a particularly useful schema of "layers" instead of successive stages in the history of liberalism, emphasizing that liberal ideas appeared at different times, originated from diverse sources, and served various purposes. 

He combines this schema with the idea of "morphology," a basic set of ideas shared by all members of an ideological family, without which, or without some combination of them, the concept of liberalism is inconceivable: control and accountability of power, freedom, rationality, belief in progress, individuality, mutual interdependence and sociability, public interest. Finally, he poses an important question: should we perhaps speak of "liberalisms" rather than "liberalism"?