This chapter provides an overview of the book. It presents the outcome of interest: the political strategies of teachers or the different ways that teachers mobilize in politics. These strategies are referred to as instrumentalism (strategic alliances), movementism (recurrent protests), and leftism (alliances with left parties). The chapter explains the significance of these strategies in relation to the labor movement and education politics, and it introduces the main argument. This chapter shows that examining the ways in which teachers mobilize in politics helps to shed light on normative questions about how they shape education policy and democratic governance.