Because of the increasing flow of excellent papers from research workers throughout the world, Journal of Statistical Physics is expanding once again. The number of pages published in each double issue in 1986 will be increased by 12 %. Therefore, Volumes 42, 43, 44, and 45 will each contain 3 double issues; the subscription rate will be $225.00 per volume (outside the U.S., $250.50 per volume).