This thesis will primarily consider what INCOTERMS stand for in International Trade Contracts according to ICC (International Chamber of Commerce). Then it reviews the importance of the International trade terms through clarifying the relation between the four INCOTERM groups and CISG, then with the Rotterdam Rules with cases to represent these relationships. It also shows the right way to refer to INCOTERMS in International trade contracts in order for it to become binding. At last it predicts the changes that will occur in INCOTERMS 2020.