The purpose is to explain, in general terms, some of the possibilities for micro, small and medium enterprises (MSMEs) to internationalize, taking into consideration, among other aspects, the elaboration of the contract, preferably written. The meaning of international trade comes from the mercantilist, classical and neoclassical currents and from contemporary postulates, such as the theory of competitive advantage, which demonstrate the importance of the exchange of goods and services for economies. International trade relations of any company are based on requirements of importing or exporting raw materials, machinery, final and intermediate goods or services procurement. However, in practice, relations can cover a wider spectrum than the abovementioned operations. This essay mentions some elements that should be considered by the parties when making the negotiation and which will be reflected in the body of the contract.