How can human-computer interaction research better integrate design with understanding? This paper presents an "action science" approach to HCI, seeking to align understanding with design activities. The approach leverages development practices in HCI with methods and concepts that support the use of design rationale, clarifying the design process's current stage, the reasons for being there, and guidance for future directions. The research reifies the process using broad and explicit design rationale. A designed artifact is represented as the set of user scenarios it supports, detailed by causal schemas that articulate the psychological rationale. These schemas, called *claims*, unpack the 'wherefores and whys' of each scenario. The research examines several empirical projects to clarify commitments and practices. Action Science aims to connect research in human-computer interaction with real-world user scenarios. This study provides a framework for thinking about HCI research as an iterative process of design, evaluation, and refinement. By emphasizing design rationale and grounding design in user scenarios, the action science approach seeks to produce more usable and effective interactive systems.
This paper, published in ACM Transactions on Information Systems, is directly relevant to the journal's focus on research and development in information systems. The action science approach to HCI provides a valuable perspective on how to improve the design and development of interactive systems, making it of interest to the journal's readership.