Escort shakes & shimmies while braking at speeds over 55mph

I have a 1999 Ford escort with 90k miles. The problem I am having now is that my car shakes when applying the brake at speeds over 55 mph. The problem seems to be getting worse the more I drive. Any ideas what might be causing this?

ur brake rotors might be warped. u might have to replace them or a shop can "turn" them. hope i have helped

I agree with kenny.Sounds like brake rotors.