The EPA's pretreatment regulations under 40 CFR 403.2 aim to control pollutants in commercial and industrial wastewater discharges to protect POTWs (Publicly Owned Treatment Works) and enhance opportunities for recycling and reclaiming municipal and industrial wastewaters and sludges. The primary objectives are: •Preventing pollutants from interfering with POTW operations, including the use and disposal of municipal sludge. •Preventing pollutants from passing through the treatment works. •Promoting recycling and reclamation of wastewaters and sludges. To achieve these objectives, the EPA mandates industrial pretreatment programs for: •All POTWs designed to treat more than 5 MGD. •Smaller POTWs receiving wastewater from industrial users (IUs) that could affect the treatment plant or its discharges. Approximately 1,600 POTWs have developed local pretreatment programs to control discharges from around 23,000 significant IUs. Key elements of these programs include establishing legal authority, developing local limits, implementing procedures, establishing organizational structure and budget, issuing IU permits, inspecting and sampling IUs, generating an enforcement response policy and enforcement strategies, and generating pretreatment reports. This presentation will delve into the comprehensive process of developing, executing, and enforcing the pretreatment program, specifically addressing emerging contaminants and preparing for future regulations on PFAS (per- and polyfluoroalkyl substances) discharges in NPDES Permits. Key steps include: 1.Updating IU Inventories: Identify IUs likely to discharge PFAS. 2.Updating IU Permits: Require PFAS monitoring. 3.Developing IU BMPs: Address PFAS discharges. 4.Creating Reduction Mechanisms: Implement strategies to reduce PFAS discharges. The presentation will focus on relationship-building with the industries, inspection techniques, and sampling and monitoring practices to achieve compliance, ultimately equipping POTW pretreatment coordinators with the knowledge needed to manage pollutants into the wastewater treatment systems and safeguarding environmental integrity. A few lessons learned will be presented to equip Pretreatment Coordinators with the process of identifying and exploring IU noncompliance and upset conditions due to IU discharges.