Since the arrival of the Congregation of the Mission in Poland in 1651, missionary priests have been actively involved in all forms of charitable work. The most famous Vincentian institutions in Poland include the Hospital for Orphans of the Name of Jesus in Warsaw (1732-1901) and the Home for Poor Boys in Kraków (1875-1939, 1945-1953, restored to the Congregation in 1992). The first one was founded by the French missionary Gabriel P. Baudouin (1689-1768), the second one was founded on the initiative of a missionary born in Lithuania, Fr. Kazimierz Siemaszko (1847-1904). The work consists of four parts: a biography of Kazimierz Siemaszko, the history of his works, one in Kraków and the other in Czerna near Krzeszowice (1900), a discussion of the ideas of Fr. Siemaszko regarding upbringing, and finally his participation in founding and organizing the work of another house in Krakow, founded by Prince Aleksander Lubomirski (1890). The article pays particular attention to the initial phase of Fr.'s initiatives. Siemaszki and their successful implementation in the period from 1875 to the death of the founder in 1904. The fascinating history of the Krakow Home for Poor Boys is richly documented, and its new chapter began in 1992.