Pairs of resumes, one for a 57-year-old and the other for a 32-year-old, were mailed to 775 large firms and employment agencies across the United States. Although the resumes presented equal qualifications, the older job seeker received a less favorable employer response 26.5% of times when a position appeared to be vacant. Vigorous enforcement of equal opportunity laws as well as initiatives to change employer attitudes are appropriate responses to such discrimination. The technique of employment testing, demonstrated in this research, can be useful in both efforts.