Since before the time of Alexander the Great trained soldiers have sold their expertise on battlefield around the World, fighting and dying in other people's wars for money, glory or the lust for violence and combat. In this book Harry McCallion explores the development of modern mercenary forces from the British SAS led deniable operation in Yemen in late 1960's, during which the Israelis were persuaded to arm the SAS led Yemeni tribesmen, through the bush wars in Africa, Britain's ill fated intervention in the war in Afghanistan right up to today's War in Ukraine. Many of the modern day British mercenaries were known to the author personally. including such notably figures as the legendary SAS Fijian warriors 'Tak ' Takevesia who, although in his early sixties shot his way out of an ambush in Bagdad and Fred 'Big Fred' Mrafano who devoted himself to the cause of the people of Serra Leone. SAS veteran .Bill Scully who received the Queen's Gallantry Medal single-handedly protected 1,300 civilians from rebel troops during the uprising in May 199 7after the Sierra Leone coup and American Vietnam veteran Major 'Mac' Mackenzie, who although badly wounded in Vietnam, rose from trooper to command a Rhodesian SAS squadron and was one of the units most highly decorated soldiers.Also included are more notorious figures like Costas Georgiou also known by his alias Colonel Callan who served in the 1st Battalion of the Parachute Regiment but was dishonorably discharged and sentenced to five years in prison for a post office robbery, later he proclaimed himself a 'Colonel' and led a group of psychopathic mercenaries in the Angolan War of Independence, before being captured and executed by Angolan forces. The book explores the roles of modern day mercenaries, who's use has expanded precisely because they are mercenaries, fighting for money and not love of country, their deaths are not seen as a patriotic sacrifice, often they go unreported and in turn helps to conceal the true tragic human cost of waging a war. As one former private military contractor recently stated to Australian TV "If you want to conquer in the 21st century…you use mercenaries, special forces, things to keep war secret and nobody's better at secret wars than mercenaries."