Abstract: A guide/drill stop in the form of a hollow one-piece cylindrical sleeve for frictional engagement with a cutting tool, e.g., a drill bit, to regulate the desired depth of a hole to be drilled. The guide/drill stop sleeve extends optionally over the portion of the shank of the drill bit inserted into the collet or chuck of the machine or drill to enable the collet or chuck to secure the positioning of the drill stop during drilling. Alternatively, in another embodiment, the guide/drill stop sleeve may cover only a portion of the drill bit such that the sleeve does not encompass the section of the shank of the drill bit received into the collet or chuck of the particular machine or drill. In general a drill stop, constructed of various materials in various lengths and diameters, to enable precise regulation of drilled holes of varying depth is provided.