Batch plant design is concerned with selecting unit operations, their operating conditions, the necessary production resources and an operating schedule. Traditional approaches to batch plant design involve a sequence of decisions taken in isolation, with manual transfer of information between design stages. Usually, in the first stage the operational details of each processing step are studied, perhaps through dynamic simulation, and then fixed. The next design stage considers the allocation of resources to each step, possibly taking account of production scheduling. The information transfer between these stages is limited, often unidirectional and somewhat ad-hoc. Here, we consider a more integrated approach to the design of batch plants, in the context of the conceptual design of a mixed batch/semicontinuous PVC plant. We describe the application bf state-of-the art multipurpose plant scheduling and simulation technology to the solution of this problem, and the transfer of data between these tools. This leads to a design that is more robust, as well as to the definition of a more rigorous design procedure.