The main objective of this Master's thesis is to determine whether the users of HNK Split are loyal to the institution and to what extent, if the introduction of a loyalty card would improve the reputation of the said institution, and what potential benefits the loyalty card would bring to both frequent theatre-goers and general public. The thesis explains in more detail the concept, methods of application and marketing goals in arts and culture; then the historical development, classification of loyalty programs and examples of different loyalty programs in customer relationship management in different sectors, with an emphasis on their application in theaters around the world. Through a survey and interviews with key marketing representatives of HNK Split, it was found that the majority of theatre audience is willing to become members of the loyalty programme, and for introducing the loyalty programme in HNK Split, the most important elements would be discounts on ticket prices and the possibility of making a reservation without advance payment. It should be noted that, in the future, a larger part of the marketing budget of HNK Split should be directed towards advertising on the web and social networks, for example, by collaborations with influencers (on Instagram/TikTok) to heighten interest of (potential) audience. In the same way, video recordings of "behind the scenes" moments, short interviews with the artists of HNK Split and the like could be shared. The results and guidelines of this thesis can be used to implement or improve a loyalty programme in the future, both in the for-profit and non-profit sectors, in order to develop and maintain a satisfied and loyal client base.