How did the idea of eugenics change business practices in the late 19th century? How was immigration affected by eugenics?

During the Progressive Era of the late 19th and early 20th century, eugenics was considered a method of preserving and improving the dominant groups in the population; it is now generally associated with racist and nativist elements as the movement was to some extent a reaction to a change in emigration from Europe rather than scientific genetics.