Despite the current prevalence of English as a lingua franca in international law, many international lawyers in countries such as Portugal, Brazil, Mozambique, and Angola have written a number of works in Portuguese. While more than ever, scholars from Portuguese-speaking countries have contributed to international legal journals and edited volumes in English, international legal scholars still insist on writing in Portuguese for several reasons. Portugal and Brazil have a long history of engagement with international legal concepts, institutions, and rules, which also stems from their long and well-established diplomatic traditions. For centuries, Portuguese international lawyers, followed by those in Brazil, have dealt with international legal issues and reflected upon them in the Portuguese language. In addition, states where Portuguese is spoken that emerged after the decolonization movement have made the language relevant, especially in several African countries. Factors related to the editorial market are also noteworthy. Portuguese-speaking countries have populations that total nearly 300 million. A stable demand exists for works written in Portuguese: a significant number of international law textbooks are written in the language. One cannot underestimate the deliberate interest shown by some scholars in writing in Portuguese to stimulate a necessary polyphony in the international legal discipline and, in many cases, to give form to acts of resistance to what is seen as the prevalence of English in the current international law literature. International law literature written in Portuguese has shown a slight preference for specific topics, such as the law of the sea, sources, the relationship between international and domestic law, and human rights. The oceans have been economically and strategically crucial for Portugal and its former colonies for centuries. Preference given to sources is due also perhaps to the strong relevance that Romano-Germanic legal systems attach to formal legal sources. As seen in different parts of the world, the growing call for domestic actors, including courts, to interpret and apply international law helps to explain the increasing volume of work on the relationship between international and domestic law and human rights. This article has three main parts. The first part deals with Textbooks, Treatises, and Encyclopedias. The second concerns specific chapters of international law in which relevant literature written in Portuguese is identifiable. Although this article is mainly focused on books, the last section is devoted to the most pertinent international legal Journals and Blogs published in Portuguese. Most of the works are written by Brazilian scholars. However, this choice detracts in no way from the quality of scholarship in other Portuguese-speaking countries; rather, it derives from an attempt to present a wide variety of works, in different subfields of the discipline, in the Portuguese language. The higher number of books and journals published in Brazil derives from that country’s population of over 200 million and, consequently, to the presence of a large legal community there. Additionally, the existence of hundreds of law schools in that country and the fact that international law is a mandatory subject in their curricula are relevant factors.