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Basic research has shown that, during the etching stage of the cathodic-arc process, metal atoms of the coating material become embedded in the surface of the substrate to be coated. If 1200-eV Ti ions are used for etching, the penetration depth may be as great as 1500 Å. Paralleling this, more recent results reveal that an unbalanced magnetron can be used to produce dense, droplet-free TiN layers in an exactly reproducible form. Hence, when the arc-mode etching process is combined with unbalanced magnetron-mode coating, the resulting coating can be expected to have excellent properties. The technical implementation of this combined technique is known as ‘‘arc bond sputtering,’’ and is known commercially as ABSTM. This article describes how the process of producing TiAl-nitride layers is used to demonstrate the advantages of metal-ion pretreatment on the adhesive strength of Ti0.5Al0.5N layers applied to high-speed steel and cemented-carbide substrates. The adhesive-strength criteria are the LC and the Rockwell indentation test. The result of this study indicates that the Ti-ion pretreatment renders the measured adhesive-strength values for the subsequent films much less sensitive to uncontrolled variations of the coating-process parameters. It is also shown how the formation of TiAl droplets during the arc-based etching process can be reduced through the use of shutters.