We provide a systematic review of the academic literature on companies’ auditor selection process, that is, the process through which companies select and hire their auditor. Some process elements over which companies exercise discretion include the decision-makers and the extent of their influence (e.g., the audit committee, the CFO); timing (initiation, duration); the procedures and decision-making approach (e.g., formal tendering, assessment criteria, documentation, evaluation); and the eventual appointment of the auditor (e.g., shareholder voting on auditor ratification). By synthesizing the research, we identify key activities, decision points, and participants’ expectations in the selection process. We also consider academic research findings in light of practitioner guidance on best practices for auditor selection. Finally, even though most of the relevant studies use archival data to infer aspects of the selection process from associations between publicly observable auditor/company characteristics and auditor appointment outcomes, we highlight the limitations of this evidence for understanding companies’ processes, and we offer suggestions for future research. Our review provides valuable insights for audit academics, audit regulators, and practitioners interested in companies’ actual practices for auditor selection and appointment.