During the week of April 27th through May 4th 1918, twenty thousand Grand Rapids women, half the city’s female population, registered for the war effort. One thousand registrars were trained to conduct a twenty-to-thirty-minute interview with each woman. Her information was recorded on a 5 X 8 card, designed and printed in Washington DC and used nationally. Unlike the male WWI registration cards, those from the women’s nationwide registration are a data-rich resource. The men’s cards were saved; the women’s cards disappeared. Grand Rapids, however, had discovered a collection of 20,000 cards housed in the Library’s attic. Since that time, due to excellent research by genealogists and other interested researchers, many new sources of cards, and new information has been discovered beyond Grand Rapids and Michigan.