AS OF 1970, MORE THAN 85 CITIES HAD INTRODUCED 911 SERVICE AND ABOUT 50 MORE HAD DEFINITE PLANS TO PUT THE EMERGENCY NUMBER INTO SERVICE IN THE NEAR FUTURE. PRIOR TO THE NEW SYSTEM, THERE WERE TWO PRINCIPAL WAYS IN WHICH THE PUBLIC COULD GET ASSISTANCE BY TELEPHONE IN AN EMERGENCY SITUATION: THE NUMBER OF THE REQUIRED SAFETY AGENCY COULD BE DIALED OR THE OPERATOR COULD BE CALLED TO REACH THE SAME AGENCY. HOWEVER, SEVERAL PROBLEMS OCCUR WITH THESE METHODS. MANY METROPOLITAN AREAS HAVE NUMEROUS EMERGENCY NUMBERS LISTED FOR THE SAME JURISDICTION, WHICH CAN BE QUITE CONFUSING TO A PERSON INVOLVED IN AN EMERGENCY CRISIS. CONTACTING THE OPERATOR, WHO MUST PUT THROUGH A SECOND CALL, TAKES PRECIOUS TIME. THE ADVANTAGES OF THE 911 SYSTEM ARE (1) THE PUBLIC IS FAMILIAR WITH THE NUMBER TO DIAL; (2) THE NUMBER IS SHORT, UNCOMPLICATED, AND REQUIRES AT THE MOST, JUST A FEW SECONDS TO DIAL; (3) NO TELEPHONE COMPANY EMPLOYEE INTERVENTION IS NECESSARY; AND (4) CALLS CAN BE ROUTED OUT OF THE CENTRAL OFFICE QUICKLY. A SIMILAR SYSTEM IN ENGLAND, OPERATING SINCE 1937, USES THE NUMBER 999. LONDON POLICE ALONE HANDLED 442,218 EMERGENCY CALLS IN 1979, ALMOST DOUBLE THE FIGURE 10 YEARS BEFORE. PHOTOGRAPHS AND A TABLE ARE INCLUDED. (PRG)