It is based in New York City, U.S. William H. Sadlier is one of the oldest family-owned publishing company in the United States.

In 1928, the company was incorporated as William H. Sadlier, Inc.[7] In the 1930s, Dinger proposed that traditional questions and answers of the Baltimore Catechism be accompanied by exercises, explanatory material, and tests.

[8] In the late 1950s, Sadlier pioneered the kerygmatic approach to catechetics, drawing upon the fourfold revelation of Jesus through scripture, liturgy, doctrine, and Christian witness.

This resulting series, called On Our Way, was developed by Maria de la Cruz with the advice of Johannes Hofinger.

Melissa Gibbons is Director of Customer Service, and William Sadlier Dinger Jr. serves as VP International Sales.