Columbia first established a school dedicated to the field of public health with the founding of the DeLamar Institute of Public Health by the University Trustees in May 1921, with Haven Emerson appointed as its Director. Instruction began in September 1922 and the granting of the Master of Science in Public Health degree was authorized by the Columbia University Trustees in 1926. The Institute was eventually renamed the School of Public Health on July 1, 1945. The name changed three more times: the School of Public Health and Administrative Medicine (July 1, 1955); the School of Public Health (circa 1973); and the Mailman School of Public Health (1998); in memory of the businessman Joseph L. Mailman, whose charitable foundation bestowed a $33 million gift to the School.

With the renaming of the School in 1973, the curriculum broadened to include advanced and specialized studies through doctoral and dual-degree programs (MPH/MBA, MPH/MS in urban planning, MPH/MS in Social Work; MPH/MS in nursing; MPH/MD, MPH/DDS). The PhD programs in epidemiology and biostatistics were introduced, along with the Doctor of Public Health (Dr.P.H.), in addition to the established M.P.H. and M.S. degrees. At the time of these records, the School was organized into the following divisions: Biostatistics; Environmental Sciences; Epidemiology; Health Administration; Population and Family Health; and Tropical Medicine.