Robert K. Ressler (February 21, 1937 – May 5, 2013) was a former FBI agent and author. He played a significant role in the psychological profiling of violent offenders in the 1970s and is often credited with coining the English term "serial killer".
Robert Ressler grew up on North Marmora Avenue in Chicago, Illinois and graduated from Schurz High School, Class of 1955. He was the son of Joseph, who worked in security and maintenance at the The Chicago Tribune, and Gertrude Ressler. At an early age Robert became interested in killers, as he followed the tribune's articles on "The Lipstick Killer". Ressler claims that he was more fascinated than afraid of this notorious killer, as other killers fascinated him in his later years with the FBI. Ressler attended two years at a community college before joining the U.S. Army and was stationed in Okinawa. After two years in the army Ressler decided to enroll in the School of criminology and police administration at Michigan State University. He graduated with a bachelor's degree and started graduate work but only finished one semester before going back into the army as an officer, having also completing an ROTC program at Michigan State.
Ressler served in the U.S. Army as a provost marshal of a platoon of MPs in Aschaffenburg, as he states in his autobiography "Whoever Fights Monsters." He was in charge of solving such cases that were; homicides, robberies, and arson. After four years in Germany Ressler decided to leave the position and was reassigned as the Commander of a Criminal Investigation Division (CID) at Fort Sheridan. He then went back to Michigan State to finish his master's in police administration, paid for by the army, in exchange for two more years of service after graduation. After he got his degree he served a year in Thailand and a year in Fort Sheridan, where he finished out his career with the army as a major, and moved on to the Federal Bureau of Investigation (FBI).