Controversy corner: Addressing the essential difficulties of software engineering

The central concept of Brooks' classic paper, No Silver Bullet (1987), is that the hard part of building software is the specification, design, and testing of the conceptual construct that comprises the essence of software. A formal conceptual framework is developed for representing all aspects of a client organization, including those that have traditionally not been addressed formally, such as culture, values, concepts and perspective. This framework is then used to gain amore detailed understanding of Brooks' essential difficulty, including a better understanding of the sources of conceptual errors, particularly in the requirements definition phase. It is shown that Brooks' essential difficulty is inextricably involved with a 2nd essential difficulty, namely, that the computer system is built by one group of people, for another group of people, who differ from them in at least one, usually very important, way, including their work activities, language, the fundamental concepts that define their work and what it is about, and the principles that form the basis for their choices in their work. Outside-In Development, a methodology for addressing these intertwined essential difficulties, is presented.