In 1925, the Committee was renamed the International Federation of Eugenic Organizations (IFEO). American eugenicist Charles Davenport was a dominant force in the early history of the body. As its president, in 1929, he wrote a letter to Benito Mussolini, then Prime Minister of Italy, warning him that "maximum speed [was] necessary" in implementing a eugenics program in Italy, because of the "enormous" danger of failing to control undesirable reproduction. The IFEO held its 9th Conference in England in 1930. Davenport led the IFEO meeting two years later in New York in 1932 at which Ernst Rüdin was selected as his successor to presidency. In the 1930s, the organization was meeting every two years, with a simultaneous Conference. By 1934, when the group met in Zurich, the original IFEO had representative organizations and individuals from Argentina, Belgium, Cuba, the Dutch East Indies, England, Estonia, France, Italy, Germany, South Africa, Switzerland, and the United States.
