From 1946 to 1975, Aristotle Onassis consolidated his position as a charismatic shipping tycoon and international businessman. During this period, he pioneered what would become the basic structure of the global shipping group. Between 1946 and 1975, he purchased 140 vessels of about 3.7 million grt and received more than two hundred and fifty million dollars of finance (in current prices) for these purchases from American banks. This chapter analyzes how he built his shipping business Empire, examining his sale and purchase (S&P) methods and showing how he constructed his fleet by gathering capital resources, and how he managed his resources and exploited the choices given. Onassis confronted both opportunity and crisis as he built his fleet from Liberty ships, and tankers despite the lack of any support from the Greek shipping milieu to whom he channelled his anger through a long memorandum called the Onassiad”. He expanded his business Empire through various conflicts. His most notorious venture in oil was through an agreement with Saudi Arabia that brought him into direct confrontation with the oil majors, the US government and the European and American shipping world.