I WAS DRIVING TO WORK IN MY 2013 TOYOTA CAMRY HYBRID LE. IT WAS EARLY MORNING RUSH HOUR TRAFFIC. ROADS WERE WET. TRAFFIC WAS STOP AND GO. I WAS PROBABLY GOING ABOUT 20 MPH WHEN VEHICLE IN FRONT OF ME STOPPED. I APPLIED MY BRAKES BUT MY VEHICLE DID NOT STOP. I HIT REAR OF VEHICLE IN FRONT OF ME. I DID NOT FEEL MY BRAKES ENGAGE. I WAS MORE THAN A SAFE STOPPING DISTANCE FROM VEHICLE IN FRONT OF ME.