Abstract: A cover structure for a pick-up truck in which a cover of flexible sheet material is supported by framework over the cargo body. The framework comprises front and rear bow frames pivoted to slides which are mounted in side rails and capable of being locked to the side rails in adjusted positions. The framework also includes supplemental frames pivoted to the bow frames. The side and rear panels of the cover are secured to the side and rear walls of the cargo body by Velcro strips. The front panel is secured to the front wall by a C-shaped channel clamp. The front and rear panels of the cover have detachable windows. The framework may be collapsed, with the cover still in place, to a stored position beneath the upper edges of the side and end walls of the cargo body, in which position a major portion of the cargo body is substantially unobstructed and available as cargo space. In preparation for collapsing, the side, rear and front panels are released and the front and rear panels preferably detached.