A rescue buoy package for use on a boat for marking the location of a person overboard and for remaining in that location until help can arrive includes an outer cylindrical tube that is mounted within arm' s reach of the ship' s helm and an inner cylindrical tube that fits into the outer tube and to which a heavily weighted cap is affixed. The cap extends downwardly over the open upper end of the outer tube keeping the contents dry and secure. The contents include an inflatable mast and a vest-type flotation device. The buoy can be packaged in a normal mode in which it must be deployed manually or in a second mode in which deployment is automatic. In the normal mode the buoy is deployed by pulling upwardly on a knob on the cap to remove the inner tube, the mast and the flotation device from the outer tube, and throwing the inner tube and its affixed cap into the water along with the mast and flotation device. If the second mode has been chosen, the buoy will automatically deploy, but only in the event of a capsize. The mast inflates immediately through the action of a water-activated valve, and the flotation device, which is connected to the mast by a line serves as a sea anchor to minimize wind-caused drift of the buoy. After use, the buoy can be repackaged.