This is certainly the best bookstore in Rio de Janeiro and probably the best in the whole of Brazil. It has a wide range of books in major foreign languages, an excellent scholarly section, as well as a complete selection of books relevant to Brazil, including Brazilian literature in translation. It also has a wide selection of used books and is next door to the also-excellent Beringela, which has an impressive second-hand selection. Its customer service department is also very helpful and can get books from the most obscure publishers. I have used them on several occasions to find things I cannot find anywhere else. All in all the best place in Rio to buy books.