The principal objective in the development of the Resource Compendium was to collect information from OECD governments and selected industries on the techniques used (or are expected to be used) to estimate releases from point and diffuse sources and for transfers and to provide a summary of this information. Another objective of this project was to provide a listing of reports and other documentation describing the various methods being used in OECD countries to estimate releases to air, water, and land. This document is Part 1 of the Resource Compendium. It describes the types of techniques used to estimate releases from point sources and how they can be applied. To the extent possible, the names and contact information for individuals who can provide reports and documents about specific techniques available in their country were included. Information for this document was obtained through a survey of OECD countries.