Unified user interface design: designing universally accessible interactions

Abstract Designing universally accessible user interfaces means designing for diversity in end-users and contexts of use, and implies making alternative design decisions, at various levels of the interaction design, inherently leading to diversity in the final design outcomes. Towards this end, a design method leading to the construction of a single interface design instance is inappropriate, as it cannot accommodate for diversity of the resulting dialogue artifacts. Therefore, there is a need for a systematic process in which alternative design decisions for different design parameters may be supported. The outcome of such a design process realizes a design space populated with appropriate designed dialogue patterns, along with their associated design parameters (e.g. user- and usage-context-attribute values). This paper discusses the Unified Interface Design Method , a process-oriented design method enabling the organization of diversity-based design decisions around a single hierarchical structure, and encompassing a variety of techniques such as task analysis, abstract design, design polymorphism and design rationale.