Reactive distillation (RD) has demonstrated potential reduction in capital investment and operating costs. However, industrial RD is still limited for etherification, esterification and cumene systems. Expensive hardware requirement has reduced the benefits of the simpler RD flowsheet. Side reactors are introduced in this work to reduce the requirement of specific hardware design by shortening the reactive section of the RD column. Using the ethyl tert-butyl ether (ETBE) system as the case study, simulation results show that a shorter RD column with side reactors produced comparable performance to that of a longer RD column. This may lead to a further reduction of the cost of the column if smaller amount of the catalyst result in a decrease in the diameter or height of the column. Therefore, RD with side reactors is a promising configuration that should be investigated during the conceptual design phase. (C) 2003 Elsevier B.V. All rights reserved.