This article describes the design of a prototype multiauthor multimedia document production (MAMMDP) system. In particular, the article concentrates on how the system's tasks were analyzed and represented during the early stages of the design. The aim of the article is to relate our ideas and experiences from the analysis and design work, in the hope that some of them may prove useful to others concerned with MAMMDP. We believe that both the processes and the products of our analysis and design work can be informative about the development of MAMMDP systems. © 1998 John Wiley & Sons, Inc.

Design-oriented frameworks are a type of Human-Computer Interaction (HCI) discipline knowledge. They are intended to support iterative 'specify-and-implement' design practice, by assisting designers to create models of specific design problems, within a class of design problem. This paper presents a design-oriented framework for a class of HCI design problem, expressed as a the planning and control of multiple task work in secretarial office administration. The planning and control of multiple task work refers generally to how interactive human-computer worksystems specify and select behaviours for performing multiple concurrent tasks. Secretarial office administration is a sub-class of design problem, in which the work supports communications of the organization commissioning the new worksystem. The framework is based on a conception proposed to support an engineering discipline of HCI. The framework conceptualizes the relationship between an interactive worksystem, its domain of work and the effectiveness, or performance, with which work is carried out. The framework was developed from cognitive science and HCI theory and an empirical case-study of an existing secretarial worksystem. The framework expresses the domain of secretarial work as the state transformation of hierarchies of abstract and physical objects, representing communications carried out by the organization. The description of the secretarial worksystem expresses the relationship between abstract processes of planning, controlling, perceiving and executing, and abstract representations of plans and knowledge-of-tasks. Planning heuristics and control rules reflect general properties of the dynamic work domain, such as external interruptions and temporary opportunities. The framework also expresses the relationship between these planning and control structures and performance. In its current form, the framework is incomplete, but illustrates an approach to the development of design-oriented knowledge. Using this type of knowledge, a designer may reason about potential solutions to HCI design problems concerning planning and control behaviours for carrying out multiple task work for secretarial office administration.

Given the number and variety of task analysis (TA) products in the human-computer interaction literature, it is often difficult to understand exactly what they contain and how they differ from each other. This paper presents a schema for the possible content of a TA product, and uses the schema to examine in detail four particular products. A comparison of these enables the identification of five suggested features for distinguishing between TA products: the psychological status of the behaviours; any fixed behaviours; the number of levels in the decomposition; any fixed levels in the decomposition; and the separation of objects and behaviours. Both the schema and the distinguishing features support the comparative assessment of TA products.

Which behaviours of an interactive work system perform the work that the system was designed to do? And what do the other behaviours do? The idea of distinguishing work tasks and enabling tasks is presented. Suggestions are made on how to distinguish them, based on a conception for human-computer interaction. Suggestions are also made as to how the ideas may be useful in the design of interactive work systems. The ideas are illustrated by the analysis of some actual user-computer interactions in the domain of text editing.

Unless it is possible to use a broadband communications terminal for directly engaging in the tasks and activities which are important to the user (without the necessity of learning complex skills like those required to operate today's workstations) uptake will be restricted and usage will be inefficient. The enabling states approach, which distinguishes between the users' goal tasks, the states of the communication system which enable the performance of those tasks, and the enabling tasks required to create such enabling states, is described. The intention is to improve usability (and hence both uptake and usage) by designing interfaces that automatically identify and create the appropriate enabling states, allowing the user to concentrate on goal tasks rather than the enabling tasks. The approach is illustrated and discussed in the context of integrated broadband communication systems.>