This year marks the 50th anniversary of the Age Discrimination in Employment Act (ADEA),[1] which was signed into law by President Lyndon B. Johnson in 1967. Congress created the legislation in an effort to promote the employment of older persons based on their ability rather than age and to prohibit arbitrary age discrimination in employment.[2] During the past fifty years, the ADEA has been amended several times, including in 1978, 1986, 1990 and 1996,[3] thereby expanding the scope of the law and the protection afforded older workers. While the overall effect of the amendments has been to expand the law, court decisions have tightened the requirements for proving a violation, and, according to the Equal Employment Opportunity Commission (EEOC), outdated assumptions about age and work persist as stereotypes and barriers to the employment of older workers.[4] This article looks back at some of the significant changes to the ADEA and legal decisions interpreting the law since its enactment.