The paper presents Marcin Kacprzak, an outstanding Polish scientist, publicist and hygienist whose life was inseparably connected with social medicine. Marcin Kacprzak, giving a speech at the Palace of Nations in Geneva on the occasion of receiving the International Leon Bernard Prize, said: ‘the issues of social medicine have always been the substance of my life’, and ‘if I could start another life, I would also dedicate it to social medicine’.

In the paper, special attention was given to the period in the creative activity of Marcin Kacprzak when, during 20 years of the interwar Poland, he persisted in raising issues of social medicine in spite of frequent opposition. In the presented publications, Marcin Kacprzak openly addressed such problems as the need for equal and universal availability of health care to all citizens of the Polish State. In order to implement his social welfare ideas he was also active as a journalist, teacher and organizer. In addition, he showed a vast interest in the problems of infectious diseases epidemiology. Marcin Kacprzak was editor of the monthly „Zdrowie” (‘Health’), and later „Zdrowie Publiczne” (‘Public Health’).

His years-long research work, achievements in the field of health promotion and education, his struggle to improve the health condition and health care availability to the Polish population, was crowned, in 1937, by being elected the fourth President of the Polish Society of Social Medicine.