This chapter introduces the academic discourse on politically connected firms, offering a comprehensive review of literature across multiple disciplines, including economics, finance, management, and political science. It delineates the conceptual evolution of political connections, framing them as mechanisms through which individuals or firms gain market advantages. The chapter situates these connections in diverse institutional contexts, demonstrating their pervasiveness across both developed and emerging economies. It also outlines the key methodological approaches and theoretical frameworks—such as resource dependence, agency, and institutional theories—that scholars use to analyze the implications of political ties. Readers will gain foundational insights into the multifaceted nature of political connections, their theoretical underpinnings, and the broad questions that guide this field of research. This literature survey sets the stage for deeper empirical and conceptual explorations in the subsequent chapters.