Abstract: A new multi-purpose portable davit anchoring system is provided, having a sectional vertical support mast which comes apart for compact stowage and is easily reassembled. The support mast incorporates a screw jack assembly which adjusts the height of the mast and biases the support mast between two opposing surfaces, such as a floor and ceiling. The biasing action enables it to be firmly yet removably attached to a building wherein the exterior walls are not load-bearing but merely sheathing, and to provide support for a damaged ceiling that might otherwise collapse. A boom member is removably fastened to the support mast, for deploying a lifting and lowering cable away from the side of the building. A mounting plate is provided for a winch assembly that can wind up the cable or release it at a controlled rate of speed.