The University of Edinburgh and research sponsors are authorised to reproduce and distribute reprints and on-line copies for their purposes notwithstanding any copyright annotation hereon. The views and conclusions contained herein are the authorâ s and shouldnâ t be interpreted as necessarily representing the official policies or endorsements, either expressed or implied, of other parties.

I-X is a research programme with a number of different aspects in-tended to create a well-founded approach to allow humans and computer systems to cooperate in the creation or modification of some product such as a design, physical entity or plan - i.e. it supports cooperative synthesis tasks. The I-X approach involves the use of shared models for task-directed cooperation between human and computer agents who are jointly exploring (via some, perhaps dynamically determined, process) a range of alternative options for the synthesis of an artifact such as a design or a plan (termed a product). The (Issues - Nodes - Constraints - Annotations) ontology is used to represent a specific artifact as a set of constraints on the space of all possible artifacts in an application domain. It can be used to describe the requirements or specification to be achieved and the emerging description of the artifact itself. It can also describe the (perhaps dynamically generated) processes involved. I-X and | have been applied to Coalition Task Support.