Bacillary white diarrhea in chickens was a major disease concern for the poultry industry during the early 1900s. Drs. L. F. Rettger and W. R. Hinshaw organized a meeting in 1928 to discuss methods for controlling this disease. In this meeting, representatives of five northeastern states discussed approaches to test for the presence of the etiological agent of bacillary white diarrhea, namely, Salmonella enterica subsp. enterica serovar Pullorum. Meeting attendees decided to have a yearly meeting of the Northeastern Conference of Laboratory Workers in Bacillary White Diarrhea. The next year, the name was changed to Conference of Laboratory Workers in Pullorum Disease Eradication, which was changed to Northeastern Conference on Avian Diseases (NECAD) in 1957. Not only has NECAD been important for the control of pullorum disease but also, starting with the fifth Annual Conference in 1932, other poultry diseases became an official part of the program. As such, NECAD served for a long time as the premier organization to present new information on avian diseases. The success of NECAD was based on the work of the many committees, which are described in detail in this review. For example, the antigen committee started officially in 1929 and remained active until at least 1987. The main task of this committee was to evaluate Salmonella Pullorum strains to be used by all participants in the pullorum antibody testing programs. NECAD started as a closed organization with participants from universities and government organizations but did not allow representatives from commercial groups until 1968 when all American Association of Avian Pathologists (AAAP) members in the Northeastern United States could participate. The journal Avian Diseases started with discussions by Dr. P. P. Levine with M. S. Cover, H. L. Chute, R. F. Gentry, E. Jungherr, and H. Van Roekel about the idea that NECAD would sponsor a journal dealing specifically with avian diseases. During the first few years of Avian Diseases publication, many articles including abstracts came from the NECAD Annual Conferences. The importance of NECAD as a precursor for other regional meetings and the AAAP and as a forum for graduate students to present their research are described. Several recipients of the award for the best paper presented by a graduate student have continued to work in avian disease research. The decline in the participation of scientists in the late 1990s and early 2000s was discussed extensively in 2006 and led to a merger of the NECAD meeting with the Pennsylvania Poultry Sales and Service Conference. Due to the COVID-19 pandemic, the 92nd Annual Conference was a virtual meeting in 2020. Fortunately, the 93rd Annual Conference in 2021 was an in-person meeting held in State College, PA.