Although a written agreement is not necessary in Mexico for a commercial transaction or a related contract to be considered valid and enforceable in court, documentary evidence is going to help you bring a stronger case upon collection, and even relieve you from having to bring witnesses into the trial, which makes for a shorter case. That is why you must support your sale of goods with a written contract, or at least try to sustain all details about your transaction with the use of key documents. Important details about the transaction include the following: 1) the debtor’s identity; 2) agreed terms of sale; and 3) performance of the parties’ obligations. Such conditions can be achieved by implementing and keeping the following documents: Credit application. This represents the most essential document to support your claim. It will be fundamental to include —among other things— terms of sale, considering CISG as well as Mexican law; debtor’s identity, including authorized personnel to make purchase orders; certification by signor about the accuracy of information provided; personal or corporate guarantees by shareholders or parent companies, etc. An original signed copy of such an application must be requested at some point during the initial stages of the transaction. Purchase orders (PO’s). Equally important is to have documents that prove that certain goods were requested (thoroughly specified), and that the buyer promised to pay on certain terms and to receive such goods on a specific location. Such PO’s are only to be considered if submitted and signed by appropriate personnel (as authorized in the credit application) and an original signed copy is received, or at least a digital copy by verified email. Receipt of goods sold. This requirement is met by requesting a proper bill of lading signed by the carrier who picks up the goods at your warehouse or facility. It is important to instruct the carrier to specify the date of delivery, and to obtain the full name of the person receiving the goods, besides his signature. If there is no carrier in the picture because the buyer is taking care of freight or transportation, a receipt for such goods must still be considered and obtained. Promissory notes. It is crucial to have debtors sign promissory notes for credit lines and for past due accounts. These are known in Mexico as “pagarés”. This helps by limiting defensive arguments and excuses a debtor may have in responding to a collection claim in court. This also enables a creditor to obtain an immediate writ of attachment upon filing his complaint. (Please contact us and request the free brochure “Pagarés: Rules You Need to Know Now for Valid Promissory Notes in Mexico.” It includes an example form).