Abstract: The invention provides a side rail assembly for use with an institutional bed. The assembly includes provision to move a vertical frame from an upper or deployed position where it is generally above the mattress on the bed, to a lowered position generally below and outside the mattress. The frame can then be moved longitudinally from the lowered position into a stored position below the mattress so that the frame will not interfere with an attendant who is assisting the patient. Further, the frame will then have no impact on access to the bed. The side rail assembly also includes a balance assembly to counterbalance the weight of the frame so that the frame is unlikely to cause accidental injury to a patient as the frame is moved vertically.