A treaty is an agreement between two or more countries that is legally binding. Treaty subjects are the topics discussed and agreed upon in a treaty. In this crossword, the solutions for the term 'Treaty Subjects' are 'BORDERS' (7 letters) and 'Testbans' (8 letters). BORDERS refer to the physical boundaries between countries, while Testbans refer to the prohibition of certain types of tests, such as nuclear weapons tests.