ON a Central Square sidestreet one evening a few months ago, I was stopped by a tall, gangly teenager.

"Excuse me, ma'am," he said. "This is a stick-up."

He whipped out a gun, led me into an alley, and watched me search frantically through my wallet. I knew I had less than $10, and I knew that muggers have a tendency to get angry when their victims have little to offer them. I was so nervous that I dropped my I.D. card and some pieces of scrap paper; he politely bent down and picked them up for me. But despite my mugger's charm and chivalry--it was the first time I was ever addressed as "ma'am"--I could not help fearing the worst: assault, rape, death.

Luckily, my mugger was not as demanding as his gun had led me to suspect. After handing over $2 and some change, I walked quickly to the Cambridge police station to give a description. A few minutes later another woman came in, without her purse and with a description of the same man; another woman walked in a few minutes after her, with the same story.

By this time I had looked at an informal street line-up and some police photographs without success. The police officer in charge, trying to temper our obvious anxiety with a little humor, responded sympathetically. "Ladies," he said. "We've got to take back the night!" Then he offered me a ride home.

PRETTY admirable, I thought, for a police officer from Central Square--not only knowing the lingo, but offering to chauffeur me home on the most crowded of streets. This police officer's concern should not have come as a surprise; after all, choosing a career in law enforcement implies a concern for the safety of the unprotected citizen.

Here at Harvard University, however, where Cambridge's Take Back the Night program is organized, the campus police are not as aware as this one Central Square police officer--and certainly not as sympathetic.

A few weeks after I was offered a ride home from Cambridge's police department, another student, Clarice Ballard, was refused one from Harvard's Why? She was using the police escort service too often--a sadly twisted reason for refusal. The University police should not have hesitated to give her frequent rides--she was returning to the same isolated home night after night and many in her neighborhood recently had been victims of armed robberies.

As the nation's only campus police allowed to carry guns. Harvard's force had better be among the most concerned in the country. Unfortunately, their reluctance to ensure student safety is matched only by Harvard's pitiful safety facilities--one unmarked escort car, no walking escort service, unguarded access to houses, and weak or broken Yard lights.

Attitudes among the Harvard community are equally apathetic, if not deliberately antagonistic, toward women's security. The final club mentality--women allowed in only for parties, as social and sexual objects, not colleagues--is as prevalent outside the clubs as in. The University's lack of enthusiasm for women--shown by the abysmal hiring record of women for top posts in the administration and tenured faculty--can only prevent the awareness of women as professional and authoritative equals.

THE danger of the clubs' and the administration's discrimination lies not only in sexual arrogance but in sexual violence. According to the University Health Services, a recent study shows that one in four college women nationwide are victims of rape. Eighty-four percent of these cases are categorized as acquaintance rape, which is rape of women expecting to be treated as equals by their male peers and one of the most difficult crimes to prosecute. At Harvard a date rape victim, who has brought her case to the Administrative Board, is prohibited from finding out if a punishment has been meted out to him.

How can college campuses, particularly Harvard, help solve the problem? Increased awareness of sexual abuse and discrimination is needed, beyond the current bare minimum of enlightenment. It is the administration's duty to support peer counseling groups such as Response; publicize sexual harassment dangers to students and seriously punish and publicize offenders; condemn, not tolerate, sexual harassment of employees like Charlotte Walters, who recently sued Harvard; accord women professors the respect they deserve with fair hiring, tenure-granting, and job-distributing practices.

And the Harvard police force must, help give back the night, by confronting the security threat in our corner of Cambridge. At the very least, the department must bolster the escort service.

All of these tactics, made more frequently and publicly than is now the case, could change Harvard's image to that of a University sensitive to the security and equality of its entire community. These are among the purposes of the annual Take Back the Night rally, to take place tonight.

At last year's march, a small squad of police escorts accompanied the participants through the streets of Cambridge. Their symbolic support was appreciated. But the next step is the real point of Take Back the Night: ensuring protection for those of us who walk through Cambridge without the company of a parade.