Sophie van Senden Theis (left) bringing Martha to Jessie Taft (right). Also pictured are Bobby Ueland (the adopted son of Elsa Ueland, another leading social worker) and Taft’s adopted son, Everett. Sophie was the first genuine adoption professional and researcher in the history of the United States. She was best known for her pioneering outcome study, How Foster Children Turn Out, published in 1924, in which Theis documented what had become of 910 children placed in homes by the New York State Charities Aid Association between 1898 and 1922. It was the first large-scale inquiry of its kind, became the prototype for many later outcome studies, and is still cited as a landmark in the history of adoption research.