This chapter considers the ways in which backbench Members of Parliament (MPs) exploit their right to introduce legislation — known as private members' bills (PMBs). The PMB process has been criticized for allegedly being opaque, misleading, and virtually discredited inside and outside the UK Parliament. Yet, each session, more than 450 backbenchers enter the Commons PMB ballot for a priority slot. The chapter first explains the terms ‘hybrid bill’, ‘private bill’, and ‘public bill’ before discussing the difference between PMBs and government bills. It also examines the importance of time when considering PMBs, the three routes to a PMB in the House of Commons, a typical second reading Friday in the Commons, and the PMB ballot in the House of Lords. Finally, it analyses efforts to reform PMB procedures and why, despite flaws and frustrations, PMBs are seen by many MPs as a useful tool for advancing their agendas and campaigns.