The thesis covers the details of small and medium enterprises, describes their organizational and legal forms and points out their importance in the national economy, not only for the Republic of Croatia, but also for other nations around the world. Through the analysis of the business of small and medium enterprises, creativity and easy adaptability are recognized as their greatest assets in competing with large companies. This adaptability plays a major role in the current crisis that has gripped the world. COVID-19 has harmed a huge part of the world's economy, including small and medium-sized enterprises. Without resources like the large capital reserves that large companies rely on, small and medium enterprises must find alternative ways to sustain their business. They are assisted in this by entrepreneurial support institutions that play a major role in maintaining the liquidity of small and medium enterprises. In addition to support institutions at the level of the Republic of Croatia, the importance of local entrepreneurial-support institutions of Virovitica-Podravina County is also reflected upon, those institutions encourage entrepreneurship and enable its growth and development. The impact of the crisis on the area of Virovitica-Podravina County was not small, many small and medium entrepreneurs have felt large losses in income, some up to a large 50%, but have not yet closed their doors. The large volume of entrepreneurs was helped by the measures of the Government of the Republic of Croatia in stabilizing business, the services of support institutions, but also their own persistence and adaptability, which includes business modification, market change and introduction of new business practices. Every crisis is an opportunity to learn, and COVID-19 has shown how important the self-sufficiency of a country really is, as well as its cooperation with important sectors of the economy.