Our research focuses on the question of acceptance of current e-government systems by elderly users. It describes how such systems should be designed and offered for this user group in order to provide an acceptable alternative to offline processes. In order to answer our research question, the research was structured into three phases along the development model of the ISO 9241-210. This enabled to identify not only the main factors of acceptance, but also the expectations of elderly users. Our research was conducted in parallel in Germany and Hungary in cooperation with the Fraunhofer FOKUS, the Federal Ministry of Interior, the Bundesdruckerei and the Corvinus University Budapest. The first phase provided results about the expectations and previous experience of the users with e-government systems. Our goal was to acquire information about the general experience of the age group with interactive applications so that a suitable test environment could be selected in the second phase of the research. The results made it possible to select an application in the second phase, which was used as a model in the remaining phases. The selected application was the AusweisApp of the electronic ID card. This was tested with 75 participants and a control group consisting of 20 students of the Humboldt-University. The obtain results allowed us to develop a generalised solution, the IGUAN guideline. This guideline makes a standardised approach to the usability improvement process possible. It contains the special requirements of elderly users, and a catalogue of criteria, which helps to develop an application in line with the set requirements. The third phase of our research was used a proof of concept for the IGUAN. The guideline was evaluated and tested with an iterative prototyping. The successful completion of this phase indicates that the IGUAN can be used to measurably increase the acceptance of e-government systems by elderly users. We could therefore demonstrate that improvements in the interface make e-government application possible which are perceived useful and easy to use by elderly users. These improvements will measurably increase the user motivation and experience. This can however only be achieved with a structured design process, and requires a framework which takes the requirements of the elderly users into account.