FOR ALL BUT FOUR OF THE INSTITUTIONS INVOLVED, A RECENT CALENDAR OF PRISONERS WAS USED TO DEFINE THE SAMPLE. THE DATES FOR THE CALENDARS RANGED FROM MAY 2 TO NOVEMBER 28, 1977. A DATA COLLECTION FORM COVERING THE INMATES' SITUATION FROM ADMISSION TO JAIL AND THEN TO EVENTUAL RELEASE OR TRANSFER WAS COMPLETED FROM INSTITUTIONAL FILES ON EACH OF THE 2,430 SUBJECTS. FINDINGS INDICATED THAT ONTARIO'S JAIL POPULATION BREAKS DOWN INTO FIVE MAIN GROUPS: SENTENCED, REMANDED, SENTENCED AND REMANDED, PAROLE VIOLATORS, AND IMMIGRATION HOLDS. IT WAS FOUND THAT THE MAJORITY OF THE SENTENCED INMATES WENT ON TO SERVE OUT THE DURATION OF THEIR TERM IN THE SAME JAIL AND THOSE WITH THE LONGEST SENTENCES WERE THE 370 WHO WERE TRANSFERRED TO ANOTHER INSTITUTION TO SERVE THEIR SENTENCE. THE LONG PERIOD OF TIME SPENT IN JAIL BY THOSE EVENTUALLY TRANSFERRED OUT POINTS TO THE PROBLEM OF THE OVERCROWDED SITUATION IN THE JAIL DUE TO TRANSFER DELAYS. THE MOST STRIKING FACT ON EXAMINATION OF THE RENAMED GROUP WAS THE SMALL NUMBER WHOSE STAY ON REMAND LED TO A SENTENCE OF INCARCERATION. THE LARGE NUMBER OF OFFENDERS (23) HELD ON REMAND ALSO COULD CAUSE THE CURRENT OVERCROWDING IN THE PROVINCE'S JAILS. INMATES BOTH SENTENCED AND REMANDED MADE UP THE LARGEST PORTION OF LONG-TERM JAIL RESIDENTS. THE RESEARCH SHOWED THAT OFFENSES LEADING TO INCARCERATION RANGED FROM BREAKING MINOR MUNICIPAL BYLAWS TO MURDER OR ARMED ROBBERY. MOREOVER, THE MAJORITY OF THOSE COMMITTED FOR SERIOUS OFFENSES WERE FROM THE REMAND GROUP. NUMEROUS TABLES ACCOMPANY THE REPORT. (MJW)