Abstract: The present invention relates to a scaffold consisting of section members, joining members, supporting shoulders and keys. The section members are provided with equidistantly spaced openings, the dimensions of which correspond to the outer dimensions of the section members. The scaffold is assembled by providing the section members, constituting the lower upright members, with support shoulders; threading section members on said upright members to rest against said support shoulders to constitute horizontal beams; by disposing a working platform on said beams; by threading guard railings through the openings of said upright members; by fixing said members and shoulders where necessary by means of keys; by joining further section members to the lower upright members by means of the joining members. The lastmentioned section members are provided with support shoulders and the above steps are repeated.