Albert Gayer (1880-1930) served as commander of the III Submarine Flotilla, from the war’s commencement to late 1917 and subsequently to the Armistice in the Imperial Navy Office dealing with submarine construction issues. His wartime operational command and leadership merits are indicated by his sobriquet, “King of the Ems”, bestowed by fellow submarine officers under his command. Gayer’s “Die Deutschen U-Boote in ihrer Kriegführung 1914-1918” encompasses four volumes narrating submarine operations to include individual patrols and summaries, technology improvements, tactics and frontline personnel views of strategies developed at the most senior military and political level. The back and forth decisions regarding using submarines to stalk warships or merchant ships are described. The work is particularly useful for presenting the views of front line flotilla commanders who are able to analyze their boat commanders’ experiences. Their perspective is useful in seeing the reasoning behind submarine deployments. The views of individual boat commanders appear in these pages. (Weddigen, Schwieger, de la Perière) Personnel who commanded support detachments and contributed to the whole are individually recognized. The original text has been faithfully translated. There are no omissions; Gayer’s footnotes and the foreword for each volume are included as are his extensive tables. Pagination is now as one complete volume rather than recommencing with each volume. Additional footnotes have been added correcting misidentification of sunken vessels in the text as well as minefield maps and various illustrations correcting or clarifying the text.