Joe Allen, authour of The Package King: A Rank and File History of UPS traces the rise of UPS as a powerful corporation and its labour-management struggles. Allen examines UPS from the perspective of rank and file trade union activists fighting for their rights, dignity and survival against what has become one of the most powerful logistics companies in the world. The history of UPS is directly connected to the history of the Teamsters union. UPS workers are the largest segment of the Teamster current membership.