In this paper, we consider what is required to develop parallel algorithms for engineering applications on message-passing concurrent computers (multicomputers). At Caltech, the first author studied the concurrent dynamic simulation of distillation column networks [19, 21, 20, 14]. This research was accomplished with attention to portability, high performance and reusability of the underlying algorithms. Emerging from this work are several key results: first, a methodology for explicit parallelization of algorithms and for the evaluation of parallel algorithms in the distributed-memory context; second, a set of portable, reusable numerical algorithms constituting a "Multicomputer Toolbox," suitable for use on both existing and future medium-grain concurrent computers; third, a working prototype simulation system, Cdyn, for distillation problems, that can be enhanced (with additional work) to address more complex flowsheeting problems in chemical engineering; fourth, ideas for how to a...