The Subsonic Aircraft: Contrail and Cloud Effects Special Study (SUCCESS) was a multi-aircraft field campaign which took place in April and May of 1996, over the Central and Western United States. The goal of SUCCESS was to learn more about Earth's radiative heat balance, cirrus clouds, aircraft exhaust, heterogeneous atmospheric chemistry and their interactions with each other. The SUCCESS results will be addressed in a series of Special Sections of Geophysical Research Letters over the next few months. Here we provide an overview of these Special Sections. ¿ 1998 American Geophysical Union