Our vision is to lead organizational changes aimed at achieving the business goals of our clients, whilst combining unique methodologies, engaging experiential processes and positive psychology.


Ernest Katzir


Co-founder of the Entropy Group, Ernest holds an Executive MBA from the Bar Ilan University. Ernest is the Group’s management and operational leader. He has over 20 years of experience in the Group’s core fields of operation and practice, as well as handling the Group’s clients with their most central challenges.


Or Brant Shalev, Founding Partner

Founding Partner

Or has been leading implementation processes, consulting and instructions in organizations for about 15 years. He has done so successfully in hundreds of different organizations from various sectors. Or lectures and trains tens of thousands of executives and employees every year and is considered to be one of the leading lecturers in the business and educational sectors. As such, he was selected to give a TEDxbgu talk. Or is a pioneer in the fields of implementation and gamification and the combining of both positive psychology and gamification theories in the organizational world. He serves as guest lecturer in universities, colleges and numerous professional conferences, and he is also a fellow member of Israel’s Forum of Positive Psychology Researchers.


Sigi Zelinger


Sigi serves as the company’s Chief Executive Officer and strategic partner. She leads its vision and strategy and directs the operational paths of achieving the company’s goals. Sigi joined the company following 25 years of service in the Israeli Defense Forces, in its human resources division. As part of her military career she served in a variety of positions in the human resources division of the IDF, both in the field and in command headquarters. In her last role, she served as commanding officer of the Jerusalem recruitment base. Through her entire career, in her special way and conviction, she handled human resources by laying down her vision and implementing it in the organization, making those changes that were necessary to meet the goals of the organization, maximizing efficiency and streamlining, providing service, empowering people and more. To this day, drawing on her vast experience, Sigi is invited to lecture before youth, educators and parents on the subjects of recruitment and placement in the IDF. Sigi holds a bachelor’s degree in political science, sociology and anthropology, as well as a master’s degree in public administration, both from Bar Ilan University.


Dr. Tamar Itzikson

Academic Advisor

Tamar is a fellow member of staff in the Peres Academic Center’s Organizational Development and Consulting Program, as well as a teaching fellow at the Ben Gurion University’s Education and Management Faculty. Tamar holds a master’s degree in psychology, magna cum laude, from the Hebrew University in Jerusalem, as well as a Ph.D. (including a post doctorial program) in Management from the Ben Gurion University in the Negev. Her research focuses on processes that lead to growth and accomplishment in the work place, such as optimism, employment strength, and meaningfulness. Within the organizational field, Tamar specializes in promoting the mental well-being of employees and executives in an ever-changing business environment. Additionally, Tamar is a qualified group moderator, with a lot of experience in leading group processes and instructing other group moderators. At Entropy, Tamar serves as academic advisor and professional instructor of our teams of advisors, moderators and executive management.

Noa Keren

Head Of Workshops And Lectures Field

Noa leads the field of workshops and lectures in the company, as well as being an instructor in the company’s unique gamification course. Noa has 16 years of experience in the field of instruction and guidance in various organizations, including governmental organizations, public companies, high-tech companies, municipalities, medical centers and more. As part of her role, Noa guides and moderates workshops as well as lectures before diverse populations of both executives and employees. Noa holds a B.A. in behavioral science as well as qualifications in organizational consulting.


Rita Gourevitch

Head Of Development And Implementation Field

Rita holds an M.A. in organizational development and consulting. She leads the field of developing implementation processes in organizations. As part of her role, she is responsible for managing and leading projects of, organizational development, knowledge implementation, change processes and behavior shaping. Rita has vast experience in leading experiential implementation processes in dozens of organizations such as, governmental organizations, public companies, municipalities, medical centers and more, from the initial phase of diagnosis, through the development and implementation phases.