The purpose of this final work is to compare bibliographic descriptions of ISBD(CR) and UNIMARC format for bibliographic data and to show whether ISBD and UNIMARC records contain the same bibliographic information for a particular publication, i.e., whether and to what extent, UNIMARC records follow the form and content of ISBD standard. The aim is to demonstrate the importance of interoperability between these standards for changing the bibliographic description format from printed catalogue card into a machine-readable record. Thus, the interoperability between ISBD and UNIMARC is examined, with the aim of identifying the possibility of a faster and more efficient transfer of the bibliographic data from the printed format into a format enabling the machine to read this data. The research was conducted by a comparative analysis method, comparing the ISBD and UNIMARC records of the serial Nautica. The bibliographic description of this publication was taken from the printed edition of ISBD(CR), while the UNIMARC record for the same publication was taken from the integrated library and information system of the Croatian libraries - CROLIST. Based on the comparison of the data contained within these two records, and the ISBD(CR) areas and UNIMARC data blocks, it was concluded that the interoperability between these two standards had been achieved.