Zlatan Dumanić was a contemporary artist and naval captain from Split, who tried his hand at all forms of art and sculpture. He was the author of a series of multimedia actions, performances and unique hand-made books, and participated in a number of group as well as solo exhibitions, and represented Croatia at the 51st Venice Biennale. After his death, his collection was bought by a private collector and close friend who instigated the inventory of the items in the collection. All 1208 items found in the artist's apartment were listed and described in the collection level description. This thesis describes a few examples of specific items within the collection, including items from the aspect of librarianship and museology with the aim of inspecting the content of the collection for easier searches and transparency. For the purpose of describing a part of the collection, the exhibition catalog "Rodrigina 2", held in 2008. was used for orientation, in the Gallery of Art in Dubrovnik. The theoretical part of the paper presents the definitions of collections by the profession and ways of building collections in libraries and museums, Furthermore, one chapter is dedicated to collectors and bibliographies because this collection is the result of a collection of contemporary art. In the final part of the thesis, plans are presented for the future of the collection and the importance of collecting contemporary art. This graduate thesis, in its essence, considers collections as the central focus of libraries, museums and private collections, and highlights the documentary importance of the collection level descriptions for recording, protecting and preserving collection information.