Cirillo was the first leader of FMCSA, a modal administration within the Department of Transportation charged with improving truck and bus safety. FMCSA came into being through the Motor Carrier Safety Improvement Act of 1999.

In an email message to staff Cirillo stated, "Well, finally the rumors are correct. I have decided to retire at the end of the year. Together we have accomplished much and I am extremely proud (personally and professionally) to be retiring from FMCSA. You are the greatest and I shall surely miss each of you."

"Ms. Cirillo, from day one has displayed a total dedication to the agency's mission of saving lives by preventing accidents involving trucks and buses," noted FMCSA spokesperson Dave Longo. "Personalities... characters like her, don't come along in government or anywhere else in life very often... She will be missed."

Cirillo’s last workday at FMCSA will be January 3, 2003.