One of my favorite papers. Incidentally, although I'd spent my entire career chasing some elusive notion of "good design", this paper was the first I have seen

One of my favorite papers. Incidentally, although I'd spent my entire career chasing some elusive notion of "good design", this paper was the first I have seen to explicitly define "good design" as "modular". It is now generally accepted that modular design is the key to successful programming... However, there is a very important point that is often missed. When writing a modular program to solve a problem, one first divides the problem into subproblems, then solves the subproblems, and finally combines the solutions. The ways in which one can divide up the original problem depend directly on the ways in which one can glue solutions together. Therefore, to increase one’s ability to modularize a problem conceptually, one must provide new kinds of glue in the programming language. Complicated scope rules and provision for separate compilation help only with clerical details — they can never make a great contribution to modularization I now tend to see all the other design principles as ways to improve modularity. Everything else is mostly just fluff.