A self-countersinking screw (10) is capable of full penetration into wood, plastic veneered wood, and cementaceous products. An alternating sequence of peripheral cutters (A, B) extend from the periphery of the underside of the screw head (11), acting in conjunction with countersink cutting edges (24) and debris receiving recesses (20). Cutter (A) has an arcuate notch (30) in the cutting face (28), cutter (B) has a rectangular notch (31) in the trailing edge. Full countersinking without tearing, cracking or dimpling of the surface is achieved.