ABSTRACT

The Delta Method is a systematic approach to usability engineering that is used within the Ericsson Corporation. The method has successfully supported usability work in a number of projects and continued to evolve during the process. We have managed to introduce usability engineering as a way to establish a solid platform of user data and to extend that platform to the other side of the design gap.

Based on a real-life case study we describe and exemplify the background information processes necessary to bridge the design gap. The central activities during the user interface design are two design workshops. During the first workshop we structure the services of the system into a conceptual model and during the second we transform the implementation independent structure into a paper prototype that reflects the future user interface.

The case study shows that a method such as Delta does not stifle the creativity that is needed to design good user interfaces. It helps to structure the work so that the combined force and creativity of a usability team can be used efficiently during the process.