Exporters of agricultural products are being required to measure and take actions to reduce greenhouse gas emissions in their supply chains by retailers and corporations in the European Union, the United States of America and several emerging economies. This document aims to guide exporters and consultants using Product Carbon Footprinting (PCF) through the process of product carbon footprinting so as to make it easier for them to understand the processes involved, improve their environmental performance and ultimately to reduce the costs for their business. It includes a general background, a typology of PCF schemes and examples, issues and problems, and a conclusion.