The manufacturing strategy literature is reviewed and it is found to centre on content and process models. However, a number of other issues are present in the literature whose relationship to the central process and content models is less clear. These include the trade-off, focus, flexibility, and generic manufacturing strategies. It is noted that the manufacturing strategy literature does not fully address product customisation. The literature relating to the interface between marketing and manufacturing is found to concentrate either on the identification of conflict areas, or on strategic reconciliation between the functions. Writers in this field do give greater emphasis to product customisation. A case-study method is adopted for the research and the design involves four firms in varying industries. The firms manufacture fork-lift trucks, microswitches, telephone switching systems and diaries, respectively. The case-studies comprise quantitative and qualitative data, and each case chapter includes case-specific analysis. The analysis of all the cases finds that customisation has a very important effect on manufacturing performance. The firms have inconsistencies within their manufacturing strategies, but these are found to rest not only on the firms' manufacturing products with different volume requirements in the same plant, but also on the fact of some of the products being custom-designed. The interface between marketing and manufacturing is found to be more complex and variable than the literature would suggest. The role that customised products play in relationships with customers also varies, although this is inconsistently recognised by the firms.Based on the case-data, a model of product customisation is proposed. This incorporates customisation, flexibility, product architecture, the manufacturing strategy trade-off and the competitive criteria.