Since counter-agreements are essentially a form of barter and a new approach for many companies, it can be difficult to establish a legally binding agreement, so any contract should be checked by a lawyer to ensure it is watertight. An agreement could even be concluded by oral insurance, while a treaty (according to the dictionary definition) requires formal ratification by a nation. Bilateral agreements are ongoing, both formal and informal. Bilateral agreements are mutual agreements between two parties. Most commercial contracts are bilateral. A unilateral contract is a contract in which only one party makes a promise to perform an agreement. This person is the supplier. These objectives are consistent with the objectives of global open access 2020, the LIBER principles for editorial negotiation and the principles of Plan S.