This chapter examines ‘Regulatory Policy’ by addressing various questions that arise in considering ‘whether’ and ‘how’ to regulate. Regulatory policy includes a range of methodologies such as cost-benefit analysis and regulatory impact assessment. This chapter focuses on the methodologies used by public regulators. This chapter discusses the methods that help regulators assess who will be impacted by regulation, whether a regulation is effective, and what its costs and benefits will be. The chapter discusses the history of regulatory policy and delves into cost-benefit analysis, regulatory impact assessment, and consultations. The chapter includes a brief analysis of better regulation policies.