Cover photograph (Copyright © 2000, American Society for Microbiology. All rights reserved.): Coexpression of a GTP binding-deficient allele of ARF6 (bottom) suppresses membrane ruffling induced by plasma membrane-targeted activated Rac1 (top) in macrophages, demonstrating that ARF6 is required for Rac-mediated ruffling at a stage distal to plasma membrane targeting. (See related article in the December 1999 issue: vol. 19, p. 8158-8168.)