A program structuring principle

A principle for program structuring is introduced. The principle follows from adopting the idea that structure in a program is realized by changing or setting particular subsets of a program's variables under certain defined conditions. Individual structural components may then be defined by changing minimum subsets of variables that permit progress. This method of program structuring is Widely applicable. Examples are presented demonstrating how the structuring principle can be applied to advantage in the implementation of several well-known algorithms.