If we consider the main reason for creation of the library catalogue as well as its main audience, it is necessary to continuously research how people interact with the catalogue (regardless whether we talk about the card or online catalogues), how they understand it (bibliographic elements), do they know how to use it, and finally, whether they manage to find what they are looking for. Taking into account the claims that today’s library catalogue has been losing its significance for the users, it is of the utmost importance that the modern library catalogue is made in such a way that it fully meets user requirements. The paper gives a short historical overview of the most important findings related to the human information behaviour in relation to the library catalogue, and, among other things, discusses various topics concerning the ways humans look for and retrieve information, such as the principle of the least effort, access vocabulary, i.e. the differences in catalogue search between card and online catalogues. With the creation of the new conceptual entity-relationship model for organization of information entitled Functional Requirements for Bibliographic Records (FRBR), which was first introduced at the end of the 20th century, together with the newest object-oriented FRBR model (FRBROO), as well as the RDA, the new cataloguing code for the Anglo-American (but also wider) library community at the beginning of the 21st century, the user aspect has become more emphasized, but also, as many authors conclude, has still remained insufficiently researched. In conclusion, the paper offers the author’s ideas about a new Croatian cataloguing code (in preparation) and the importance of implementing all the previous knowledge regarding the user aspect of information seeking and searching into it.