Yung (Center for Naval Analyses) provides a rare professional's version of an aspect of the Allied invasion of Normandy that literally made all the difference. Operation Overlord, the codename for the invasion, was years in the making but the development schedule of "gators" or amphibious vehicles was always an integral part. Yung locates that development within the overall operation, and describes in detail how planners decided how the different craft were to be used to move against the shoreline. Young's maps are very helpful, showing how far the invasion force had to come from significant distances, thus making the achievement of the gators even more impressive. Yung's material on the lessons learned is fascinating for many reasons, including how planners communicated with gator personnel to make changes. Yung is also careful to give proper credit to the UK planners, gator designers and troops. Annotation ©2006 Book News, Inc., Portland, OR (booknews.com)