Developed under USAID’s Leadership in Public Financial Management II (LPFM II) project, this Customs Modernization Handbook aims to provide a comprehensive guide for Customs agencies to develop an active risk management analysis framework in the cargo processing environment. This handbook complements USAID’s Establishing Risk Management/Cargo Selectivity Capability Handbook (2004), the first in a series of Customs handbooks developed from 2004-2011, including additional handbooks by Nathan Associates on Authorized Economic Operators (AEOs) and Post-clearance Audit (PCAs) Programs. The 2004 handbook provides a general plan of action for creating a specialized staff in Customs called a Cargo Selectivity Management Team (CMST). This 2018 handbook provides technical guidance for the CMST to conduct risk management while integrating best practices from various Customs agencies and other border management agencies. The 2018 handbook also discusses risk management in the context of the WTO Trade Facilitation Agreement and innovative techniques and digital tools available to Customs agencies.