A medical waste disposal container includes a hollow container portion to contain medical waste and having a top cover (14) provided with an opening (16) through which medical waste can be inserted into the container portion. The medical waste disposal container also includes a closure to close the opening. The closure is slidable in a plane between positions in which the opening is open and closed. The top cover (14) has a major surface (20) and a recess portion (22) in which said opening is defined so as to be spaced from the major surface whereby when the medical waste container is in an inverted condition, the opening is situated above and spaced from the major surface. If the medical waste container is inverted such that the top cover forms the lower end of the medical waste disposal container, a space is provided in which liquid can pool below the level of the opening and closure reducing the likelihood of liquid leaking from the medical waste container past the closure.
