ENCorporate social entrepreneurship can be defined as the application of personal and professional competencies, including instruments to manage effectively and efficiently activities to meet requirements through the appropriate application and integration of processes so that all interested parties are aware of their role, responsibility, and contribution to the sustainable socio-economic enhancement (EMBRACE, 2020, 2021). In this case, corporate social entrepreneurship facilitates resolving sustainable socio-economic issues, delivering sustainable products and services based on social responsibility principles, meeting sustainable business objectives through sustainable optimization of organizational resources, and satisfying external and internal stakeholders' expectations. However, previous scientific studies showed that public and private companies were still considering that their companies' leadership was not aware enough of the importance of corporate social entrepreneurship principles and values. This study explores the main particularities of corporate social entrepreneurship in Lithuanian companies through experts' evaluation of corporate social entrepreneurship in public and private sector organizations.The research methodology consisted of qualitative and quantitative research methods, including expert evaluation performed by surveys (structured questionnaires) and in-depth interviews. Data gathering from benchmarking of good practices of corporate social entrepreneurship in public and private organizations, the survey (structured questionnaire), and interviews illustrated social entrepreneurship significance in Lithuanian companies in terms of one case analysis practices. Expert evaluation results showed a lack of human resource practitioners qualified in the corporate social entrepreneurship area and the vital need for educational courses and programs in this field. Keywords: entrepreneurship, social entrepreneurship, corporate social entrepreneurship, corporate social responsibility, case study, Lithuania, public and private organizations. [From the publication]