The goal of the Boreal Ecosystem-Atmosphere Study (BOREAS) was to improve our understanding of the interactions between the boreal forest biome and the atmosphere in order to clarify their roles in global change. This introduction briefly describes the papers within this BOREAS special section, the third in a series in the Journal of Geophysical Research-Atmospheres, and how they relate to the overall BOREAS Guest Investigator program, the final phase of the BOREAS experiment. The major contributions of BOREAS are also summarized, and future directions are identified. ¿ 2001 American Geophysical Union