Modern views of freedom of contract recognise that the principle of party autonomy has a number of restrictions, such as the doctrines of public policy [ordre public], of good faith [bona fides], evasion of law [fraude a la loi], and mandatory rules [with various interchangeable expressions such as lois de police, lois d'application immediate, lois d'application imperative, loi d'application necessaire, lois d'application directe]. The concept of mandatory rules is regarded as one of the key concepts in post-war private international law, existing in various legal systems, and also in some regional and international conventions, thus influencing the functioning of conflict of laws rules. It has become in recent years one of the most debated topics, particularly in continental private international law, with no agreed criteria which identify with any precision the rules which qualify for such categorisation. Dr Ebrahimi's new work is a comprehensive study of the concept, function and application of mandatory rules in international contracts and their relationship to other institutions restricting the party autonomy and a free choice of law, in the light particularly of the Rome Convention on the Law Applicable on Contractual Obligations, 1980. Dr Ebrahimi, the associate professor of international law, in Tehran Azad University and also director of Legal & Contractual affairs of PEDEC/NIOC, is aiming at the citizens of a shrinking world, where trans-national contracts are born in the blink of an eye. But in the eyes of whose law are they enforceable? Which set of mandatory rules must be totally excluded? Does the 'unruly horse' of public policy have a role to play? Is the very concept of 'mandatory rules' a moribund one? And what are the faults of article 7(1)- the 'difficult donkey' of the 1980 Rome Convention? The achievement of this detailed and scholarly work is to explain the conflicting/overlapping terminologies clearly, and use statutes, case law and academic sources to clarify points of difficulty arising from the articles of the Convention, without, of course, losing sight of its stated function, namely to unify the business world rather than fragment it. This scholarly work and valuable guide is a welcome addition to textbooks in the fields of private international law, conflict of laws, international commercial and trade law, consumer and employment protection laws; and a commentary to fully understand the regional and international conventions on private international law, particularly the Hague Conventions on the Law Applicable to contracts for International Sale of Goods 1955 and 1986, the Mexico City Convention, 1994, and the Rome Convention on the Law Applicable to Contractual Obligations, 1980, and also a useful pointer to shape international contracts to come.