This dissertation sets out to study the cross-default clause under Brazilian law. Originating in the legal tradition of Common Law countries, this clause grants the creditor the discretionary right to demand early repayment of a debt or even to terminate the contractual relationship upon the ocurrence of certain events of default arising from other obligations of the debtor, which indicate a heightened risk of breach of contract in which the clause is inserted. The clause thus plays an important protective role for the creditor; however, its operation creates a delicate situation for the debtor: an event related to a specific obligation may effect a series of other obligations connected through cross-default clauses, potentially triggering a domino effect that may lead the debtor into insolvency. There is an inherent tension between the creditor s legitimate interest in security and the potentially harmful effects the clause may cause. In this context, and considering that the inclusion of such clause results from parties contractual freedom, the central question guinding this dissertation is wether there are limits to its stipulation. To address this issue, the dissertation is structured in three chapters: the first examines the structure of the clause as commonly used in Common Law jurisdiction and increasingly adopted in Brazil; the second analyzes the functions performed by the clause within Brazilian legal system; and the third explores the limits imposed on contractual freedom, both with regard to the stipulation of cross-default clauses and to the concrete exercise of the legal position they confer upon the creditor. The research is conducted using the logical-deductive method, based on the analysis of Brazilian and foreign legal scholarship on the subject.