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There is considerable pressure on the U.K. clothing industry to remain competitive in the face of foreign competition. Market forces and the trend of decreasing contract sizes have produced perceived problems with current methods of production which, coupled with the inertia to radical change, justify research. Computer simulation is an established production management tool but its potential in clothing manufacture could not be inferred. Concentrating on progressive bundle systems as the dominant method of production, this research considers the capacity of simulation in this context. Factory-based studies identified factors affecting system performance which allowed a conceptual model with high face validity to be defined. The requirement to handle complex supervisory control strategies led to the identification of visual interactive simulation as an experimental route. A computerised model, with an appropriate user interface and reporting facilities, was developed in the ~Siman si@ulat~£~~Dguage __ This was supported by animated graphics which played a substantial role in the attainment of face validity. Replication was considered to be essential for sound estimates of system performance to be obtained from this stochastic model but, as interactive control works against replication, steps were taken to reduce compromise. Software development facilitated an experimental technique that employed interaction to develop a control strategy, which then became embedded in the model for replication. By providing control consistency between replications, a more reliable assessment of system sensitivity to stochastic variability was possible. Pilot runs and single factor analysis enabled the effect of controllable factors on system performance to be quantified. Supervisory control was found to have a major effect on system performance so that the need for consistency in interaction was amplified. Considering alternative experimental methods and the practical use of the model, application areas for simulation in the absence of real time data capture were identified and demonstrated. Each application offered significant advantage over currently available planning methods and the use of simulation was supported. Information from the model can be gained about the design and control of progressive bundle lines at the pre-production phase, and the output of performance indicators can be useful in assessing real production lines. The evidence presented by this research illustrates that animated simulation can provide insight that is otherwise unobtainable.