Jeffrey A. Willick died in a tragic accident on June 18 this year.

Jeff's work on peculiar velocities, large scale structure, and cosmology were significant, and he recently began to contrubute to cluster physics as well. For several years he had planned a project to identify optically and study clusters out to high redshift using existing image data bases, notably those taken by Saul Perlmutter's high redshift supernova search, to be verified with the Hobby-Eberly Telescope in west Texas which was soon to be commissioned. Work in earnest began in the fall of 1998, and it became officially the Stanford Cluster Search soon after (see contribution by Thompson, Willick, and Mathiesen). Other related topics grew out of this interest in clusters, including looking into the effects of early-universe non-Gaussian matter distributions on cluster abundance.

This new project was only one of many. He had attracted undergraduates and graduate students to carry out research on several different extragalactic topics. He took mentoring very seriously, and took under his wing students at many levels, from graduate students working toward their dissertations to visiting undergraduates on summer vacation. He was an excellent teacher-in the classroom, individually, and in public forums.

He appeared to take on much more than he could ever handle, but he did handle it-his energy and broad expertise were impressive. His efforts to build up the astrophysics group had a major effect on this otherwise sleepy corner of the Stanford Physics Department.

And no trubute to Jeff would be complete without mention of his family-his wife and two children-to whom he was deeply devoted.