Surface coatings provide designers with increased opportunity to select the materials most appropriate for particular applications. They can be applied by various methods including physical and chemical vapour deposition. Of these methods ion plating has received the greatest interest owing to its flexibility in terms of depositing any material, whether single or alloy, its adhesion and its throwing power, and because of cost and ecological considerations. This paper reviews the science and technology of ion plating and describes the current industrial applications of this process in different fields.