Johannes Monrad Aagaard (29 April 1928 – 23 March 2007) was a Danish theologian and evangelist. He was a professor of missiology at the University of Aarhus and was active in the Christian countercult movement as the founder of the Dialog Center International, an international educational organization concerned with groups it defines as cults and other new religious movements.
Aagaard had travelled to Asia and was concerned about Buddhism and other Eastern religions, which he felt were gaining influence in Europe. In 1973 Aagaard founded the Dialog Center which was later greatly influential in promoting a negative public opinion of cults in Denmark and other European nations. He regarded Scientology as being especially dangerous, but later in his life stated that Islam was an even greater threat. Other concerns included Satanism and New Age groups. Aagaard cooperated with both religious and secular anti-cultists, but opposed deprogramming of cult members since he felt that it was ineffective and often counterproductive. He retired from the Dialog Center in 2002.
- Mission, Konfession, Kirche: Die Problematik ihrer Integration im 19. Jahrhundert in Deutschland, Gleerup, 1967
- Missions from the north: Nordic Missionary Council, 50 years, co-author with Carl F. Hallencreutz, Universitetsforlaget, 1974
- New religious movements in Europe, co-author with Helle Meldgaard, Aarhus University Press, 1997
- Identity in conflict: classical Christian faith and religio occulta, co-author with Moti Lal Pandit, Helle Meldgaard, Mike Garde, Munshiram Manoharlal Publishers, 1998
- The hidden way: a study in modern religious esoterism, co-author with Moti Lal Pandit, Munshiram Manoharlal Publishers, 2002
- In memoriam: Johannes Aagaard (1928-2007), Massimo Introvigne, CESNUR, 2007
- Contemporary missiology: an introduction, Johannes Verkuyl, W. B. Eerdmans Pub. Co., 1978, page 26
- Sharing Jesus in the Buddhist world, David S. Lim, Steve Spaulding. William Carey Library, 2003, pages 57-66
- Exploring New Religions, George D. Chryssides, Continuum International Publishing Group, 2001, ISBN 0-8264-5959-5, ISBN 978-0-8264-5959-6, page 353
- Rothstein, Mikael in Regulating New Religion in Denmark in Regulating religion: case studies from around the globe, edited by James T. Richardson, Springer, 2004, ISBN 0-306-47887-0, ISBN 978-0-306-47887-1, pages 229-231