In the product flow planning field today, we enjoy the fruit of some of the best mathematicaland practical minds (and some that are both) of the twentieth century. Every one of thetechnologies discussed in this chapter is valid in its appropriate context, and most are fullysupported today in packaged, licensable software and services.

We have achieved what feels like a certain stability of planning technology here at thebeginning of the twenty-first century. The underlying computer architectures continue to face newquestions (see Chapter 8): Should planning tools really be thin-client, web browser basedapplications? Will web services fundamentally change how applications are integrated? But most ofthe planning concepts and functional technology that we work with (the kinds of things we havereviewed in this chapter) are fairly mature at this point from a logical perspective. That is notto say that they will not change further as new concepts are invented, but we have a much betterfoundation today than we did, say, twenty-five years ago.

One of the theses of this volume is that our planning options are no longer severely limitedby communication or computational power. Do we have the technology today to take all known data andinstantly generate a globally optimal plan (assuming that we would want such a thing)? No, but wehave the technology to solve most of the problems we might care to solve. We know what simulation,heuristic, and optimization-based solvers can do for us. We know what inventory theory can do, whatMRP does, and where...