The subject of this thesis is to consistently determine and explain all relevant, theoretical features and factors related to the possibilities of career development within small and medium-sized companies using individual development plans in the Republic of Croatia, and employee satisfaction using them on the example of the company ZEZ. The aim of the work derives from the subject of the thesis, set hypotheses and research questions, and is determined by proving the connections and interdependence of employers and employees in the direction of employee career development as well as company development during this process in order to better understand how the quality and efforts of the employer related to individual development employee plans within small and medium-sized enterprises, contribute to the satisfaction of the employees themselves, and to the development of the organization as a whole. Also, show the importance of employer branding - which results in the attraction of talents and experts, and their development within the company, which contributes to the increase of human capital. In the theoretical part, it was established that in all aspects, speaking of the company's long-term business, employer branding in individual development plans, positively affects the career development and satisfaction of employees, and the overall business of the company in which they are applied. Employer branding also contributes to the positive image of Green Energy Cooperative as an employer, which is also shown by the number of professionals within it. Green Energy Cooperative has significant human capital, which makes it a successful and leading Croatian organization in the field of civic energy. The theoretical and practical part of the use of Individual Development Plans within the Green Energy Cooperative had to be supported by empirical research. Through the survey, respondents expressed their satisfaction with the current situation related to their careers after the implementation of Individual Interviews and Individual Development Plans. Using the results of the survey, the Green Energy Cooperative can recognize its opportunities to increase the satisfaction of its employees, but also turn certain shortcomings into an opportunity for its better positioning on the market. In today's time of globalization, sudden changes, but also great competition, it is necessary for a company to develop and grow in the market. The theoretical and empirical part confirmed that the company can improve part of its operations by using Individual Development Plans for the development of the future careers of its employees and their satisfaction in certain changes that the new and larger market requires.