Stings conducted by the Cook County Sheriff's Department and several suburban Chicago police forces led to the arrest of 73 potential sex buyers.
Authorities say among those arrested was a man charged with child endangerment for having his 5-year-old child in the back seat of his vehicle while he solicited an undercover officer.
The Lake County Sheriff's Gang Task Force also conducted a sting, resulting in the arrest of eight men, all charged with solicitation of a sex act.
The efforts were part of a nationwide crackdown on sex-trafficking that resulted in the arrest of at least 473 sex buyers by law enforcement agencies across 12 states.
In a statement, Cook County Sheriff Tom Dart said the National Johns Suppression Initiative is designed to target and reduce the demand for purchased sex. He said the sex trafficking industry perpetuates violence, exploitation, mental illness and drug addiction for victims.