A successful supply chain ensures continuous supply of safe, efficacious and quality-assured medical products. To achieve this, it is important to country generate accurate forecasts of program requirements, procure according to the supply plan and monitors in-country stocks to avert shortages. Additionally, quantification results can be used to advocate for resource mobilization at region and national levels, help maximize use of available resources and inform manufacturer production cycles and supplier shipment schedules. This course will provide an introduction to the key concepts and methodologies for quantification of essential medicines needed for public health programs.