It was founded in 1963[3] in Tottenville, Staten Island[4] by Daniel Harold Casriel along with Monsignor William B. O'Brien, a Roman Catholic priest and founder and president of the World Federation of Therapeutic Communities.

[5] Ron Brancato from the Pelham Bay area of Bronx New York, Program Director and former resident of Synanon, California.

[2][6] Father William B. O'Brien included Synanon's confrontational approaches, such as "attack therapy" and "behavior modification", in his addiction treatment methods.

Considered one of the most successful programs of its kind, it is described as "a supportive emotional community in which people feel secure but at the same time are held strictly accountable for their behavior".

[12][13] It was during a 1980 visit to Daytop Village that future first lady Nancy Reagan initially became aware of the drug epidemic in the United States and the toll it was taking on the nation's youth.