The article considers the latest publication of a set of documents on the history of Russian-Spanish relations in the late 1660s, carried out by V.A. Vedyushkin and E.E. Rychalovsky and featuring B.N. Florya, O.V. Volosyuk and other major Russian researchers. The author of the article notes the numerous advantages of the publication, points to its innovative nature, and draws attention to the specifi c research prospects that this detailed work provides for a wide range of scientists. The collection occupies a prominent place among the publications of sets of documents and closes a noticeable gap in the studies of Russian- Spanish relations of the Eearly Modern period carried out in recent years. This publication can be considered unique due to the fact that the presented materials allow comprehensive study of the first fully fledged Russian embassy to Spain, as well as the identifi cation of the features of both the Russian and Spanish views on the events. The collection is accompanied by supplementary materials, which are highly professionally compiled and exceptionally detailed. These are, first of all, introductory articles reviewing Russian-Spanish relations and the personality of P.I. Potemkin, as well as annotations to the documents and end notes on a number of individual but relevant issues. All these texts provide scholars with extensive new data. Even more new information awaiting its researcher can be found in the first published sources of Russian and Spanish origin, thus introduced into scientific circulation. They not only provide an opportunity to comprehend the goals, course, and results of P.I. Potemkin’s embassy as well as the embassy ceremonial, but also contain vivid details for studying the reciprocal views of Russians and Spaniards (including in a historical retrospective) and even the self-awareness of the ambassadors. The published documents are a rich source of evidence about the daily routine and manners of the Russian ambassadors in Spain, the difficulties they encountered on the way, and the range of everyday problems that they had to solve. Of exceptional interest is also the information related to economy.