Complex design procedures for a continuous and for a single product batch plant were compared. Production rate, process structure and energy integration which influence desision-making about continuous or batch operating mode, were considered. The final conclusion after applying economic analysis to all variants with single-purpose equipment is that a continuous plant with recycles after energy integration is more profitable than a batch one for all capacities, unless special reasons exist why reactors should be operated the batch way. An example calculation for a process which is planned to produce a specialty product with three reactions is used to compare the net present worth of continuous and discontinuous operation modes.