This is a detailed genealogy of the family of the 40th U.S. President, Ronald Reagan. The work is divided into thirteen parts, one each for President Reagan's paternal line (that of Michael Reagan of Tipperary, Ireland) and the twelve allied families of John Baker, Benjamin R. Bechtel, Johnnie Blue, George Bristle, Henry E. Gerdes, Eilt Habben, Samuel Luckett, William McFarlane, Nathaniel Pierce, Jacob Smith, Andrew Wilson, and Claudio Wilson (whose connection is still unproven). Dr. Gronner presents each line in Register style, followed by a kinship report that states the relationship of every person in the allied family to its head. The author compiled most of his information at the Odell Public Library and the Whiteside County Courthouse in Morrison, Illinois, which is not far from Tampico, President Reagan's birthplace. He also incorporated findings from secondary sources, including the work of respected genealogists like William Reitwiesner, Gary Boyd Roberts, Michael Pollock, David Williamson, Nancy Grubb, and others--much of which is available at the Tampico [Illinois] Historical Society. An informative Introduction explaining how this project evolved, as well as a complete name index at the back, round out the publication.