once war was declared, williams' team immediately began testing and recording the blood groups of all soldiers prior to embarkation, so that blood transfusions could more efficiently be performed in the field. in the first year of the war alone, her team, working as volunteers and in addition to their daily laboratory work, performed blood typing for 13,000 soldiers of the second australian imperial force. by the end of the war, williams' team had performed blood typing for nearly 250,000 soldiers and numerous blood donors, all on a volunteer basis.