Under the pressure of ever-increasing competition companies are implementing relationship marketing strategies in order to establish long-term and profitable customer relationships. At the same time, the sports industry is experiencing massive growth and simultaneously marketing in sport is developing as a specific discipline of marketing. Just like other companies on the market, sports associations / clubs apply a membership model as part of relationship marketing to create a long-term, profitable relationship with customers / supporters. This research has examined factors that affect members' satisfaction, whether there are differences in consumer attitudes and behavior between members and non-members, and whether certain factors affect the identification of members with the organization. The survey was conducted on 207 HNK Hajduk fans, some of whom are members and some are non-members. The survey was conducted using a questionnaire that was shared over the internet and in person. The results of the research have shown that the satisfaction of the members is more affected by the involvement of members in the work of the club than by club’s first team performance, that members are larger consumers of club products than non-members with a higher probability of long-term purchases and that there is a positive direct link between member identification, organization satisfaction, organization reputation, frequency of the contacts with organization and satisfaction with the benefits that the organization provides to its members.