Under the leadership of Professor Vito Vanoni from the California Institute of Technology, ASCE Manual 54 "Sedimentation Engineering" was published in 1975. This volume became the main reference in the field of sedimentation in the United States and worldwide. Substantial progress has been made in the field for the last 30 years to warrant the preparation of a second volume, which would complement the outstanding original one. A Task Committee has been working since 1991 to bring Volume 2 of Manual 54 to completion. The motivation for preparing it and the chapters included in the new volume are presented in this paper. With the original Manual 54, Professor Vanoni set up a standard that has been difficult to reach and hard to emulate. The companion volume builds on Vito Vanoni's legacy, reflecting his keen interest in understanding the mechanics of sediment transport as well as his love for river processes and sedimentation engineering. This paper presents some of the challenges and opportunities in the field of sedimentation engineering, the contributions of Vito Vanoni and his legacy to the profession, the history of Manual 54, and the outline of the new volume to be published by EWRI/ASCE. This second volume will be dedicated to Professor Vito Vanoni, the energetic and visionary editor and contributing author for the original volume of Sedimentation Engineering, now a classic reference.