Current human factors input to system development is effected through methods, tools and guidelines. Although the input prompts the consideration of human factors concerns during system development, reports have highlighted inadequacies with respect to the scope, granularity, format and timing of the contributions (see Smith, 1986; Chapanis and Burdurka, 1990; Sutcliffe, 1989; etc.).

To improve the effectiveness of human factors input to system development, problems with existing approaches need to be examined. Such an examination would:

1. highlight requirements pertaining to the role of human factors in system development; such as the concerns of the ‘who’, ‘what’, ‘when’ and ‘how’ of human factors input;

2. support the enhancement of existing approaches for human factors input;

3. facilitate the specification of new and more promising solutions to existing problems of human factors input.

This book argues that current problems of input to system development cannot be solved by early human factors involvement alone. Instead, it is emphasised that the problems would be solved only by ensuring early human factors involvement that is then continued throughout system development. To achieve this objective, human factors designers must also contribute actively to system specification as opposed to system evaluation only. In addition, the requirements and activities of human factors specification should be made explicit. Thus, both software engineering and human factors needs may be represented and accommodated appropriately by an overall system development agenda. Intersecting design concerns between the disciplines may also be identified and addressed more effectively in this way.