Sustainability of (small and medium-sized enterprises) SMEs in a globalized economy depends on several factors. According to available studies, effective Customer Relationship Management (CRM) is one of the factors affecting the competitiveness of SMEs in a positive way. This paper is focused on creating customer databases and on using the CRM strategy in SMEs in Slovakia. The aim of the paper is to cluster SMEs in Slovakia based on using customer databases and CRM and to identify differences in clusters according to the selected attributes. The outputs of the research focused on marketing communication and on creating the CRM strategy in Slovak enterprises are presented in the paper. Quantitative nonexperimental research using the questionnaires was conducted at the end of 2017 and throughout the year 2018. The research results are based on the responses of 1009 Slovak SMEs. Basic descriptive statistics, K-means cluster analysis, Analysis of variance (ANOVA), and Tukey HSD test were used to process the data. The resulting clusters show three typical attitudes of Slovak SMEs to creating the database, using the CRM and its effectiveness. Moreover, attitude to the application of ethical principles and holistic, integrated, and socially responsible marketing are presented in the clusters. Following the results, the fact that SMEs can be divided into the three following clusters with equal size can be stated: 1st cluster (in 92.2% and consisting of micro- and small-sized enterprises), customer databases are created for the purpose of marketing communication; 2nd cluster, consisting of the highest percentage of medium-sized enterprises and enterprises with foreign equity participation using the customer databases and CRM; and 3rd cluster characterized with smaller-sized enterprises with domestic property not focused on marketing communication and using the customer databases. The research results provide the basis for further research and support for small and medium-sized enterprises.

The service sector has become the dominant sphere of market economies over the last forty years. The maturity of a country’s economy is directly related to the maturity of services as an economic sector. The immense growth across the service sector has also put mounting pressure on the competitiveness of service enterprises and their marketing activities. The turn of the millennium has already seen the competitive struggle affected by two crises – first, an economic one and now, one caused by the Covid-19 pandemic, which has had a great impact (not only) on the service sector. The article deals with the question of how Czech service enterprises reflect on the impact of the pandemic. The article’s aim is to find out how service enterprises perceive the impact of the Covid-19 crisis depending on their size and classification within the service sector and how they approach marketing investments during a pandemic crisis. The research is focused on service enterprises (n=90) in terms of their application of marketing processes in the conditions of the Czech Republic in the period 2020-2021. The results, based on descriptive and inferential statistics (ANOVA test in conjunction with Hochberg and Games-Howell tests, Pearson’s correlation coefficient and chi-squared test), show that smaller enterprises tend to be more affected by the effects of government measures in the context of the Covid-19 crisis than medium and large enterprises.