Abstract: An apparatus for hoisting materials and placing concrete, having a non-rotating mast and a boom which is swingable horizontally and vertically, and consists of boom segments pin-jointed together in line so as to be foldable only downwardly. A line of concrete transport piping extends from the base end of the boom to the free end thereof, and a line of hoisting sling extends from the base end of the boom to the free end, hangs down to hold a load handling block, rises up and extends back to the base end, each such line being supported alongside of the boom. In service for hoisting materials, the boom is stretched and fixed at each pin-jointed connection for reinforcement by releasable pin-fastening members, whereas in service for concrete placing, the hoisting sling is raised up and seized in place to avoid interference. The apparatus is remotely controllable.