The 1990 Aspen Winter Astrophysics Conference devotes one week to the Physics of the Cosmic Microwave-Submillimeter Background. The Aspen Winter Conference Series began in January, 1985 in recognition of the fact that there was no winter conference series in the United States emphasizing a balances combination of theoretical and experimental results. The series is modeled after the highly successful French series known as the Recontre de Moriond, which has operated for more than twenty years. Each Aspen Conference provides, for approximately 65 participants, six days of close interaction where detailed problems can be discussed. This is the sixth year of Aspen Winter Conferences, which have proven exciting and highly successful.
