This study is a critical analysis of the various opinions of why museums should digitize their heritage collections. The aim of the study is to break these opinions down and critically analyse them in order to increase our understanding of why digitization is a desirable activity in museums. The purpose is to contribute to sustainable digitization works in the future. The opinions analysed in this study have been identified from three main sources: previous research; official policies and guidelines; and through interviews with the staff at Nationalmuseum in Stockholm, Sweden.  An argument analysis was conducted to identify the main positive and negative opinions of digitization. A theoretical perspective based on the societal development from modernity to postmodernity was incorporated into the analysis to uncover why these particular opinions exist. The study shows that while several issues with digitizing the cultural heritage of museums were acknowledged, the attitude towards digitization was predominantly positive. The negative opinions and fears of digitization, such as the potential loss of the physical experience turned out to be either unwarranted or solvable. The positive effects of digitization, such as increased accessibility, outweighed the negative issues. The opinions found in the previous research and the official policies reflected those of the staff who had been working with digitization in recent years at Nationalmuseum. Analysing the opinions showed that digitization is essentially a postmodern activity that caters to the needs and aims of the postmodern society. The reason why museums, that are traditionally modern would resort to a postmodern activity such as digitization is because digitization does not in fact undermine the authority of the museum, but rather helps this institution to fulfil its role and stay relevant in a postmodern society. This study is a two-year master’s thesis in Museum and Cultural Heritage Studies.