Environment Evolution: The Prism Model of Changes

A software development environment supports a complex network of items of at least the following major types: people, policies, laws, resources, processes and results. Such items may need to be changed on an on-going basis. The authors have designed in the Prism project a model of changes and two supporting change-related environment infrastructures with the following key features: separation of changes to the described items from the changes to the environmental facilities encapsulating these items; a facility, called the dependency structure, for describing various items and their interdependencies, and for identifying the items affected by a given change; a facility, called the change structure for classifying, recording, and analyzing change-related data and for making qualitative judgments of the consequences of a change; identification of the many distinct properties of a change; and a built-in mechanism for providing feedback. The author's approach to the problem of change and its rationale is described. >