Prostate cancer is one of the most common types of cancer in men: In Switzerland, each year, about 6’000 men are diagnosed with prostate cancer. Men with early-stage prostate cancer are faced with difficult decisions. They are confronted with different treatment alternatives, each with its own benefits and risks. Therefore, a comprehensive information provision is very important to facilitate patients’ participation in the decision-making process. The aim of this study was to develop and evaluate an E-Health tutorial for men diagnosed with early-stage prostate cancer. We followed a human centred design method for the software development. This iterative process used two focus groups with patients and urologists. The finals version of the tutorial was then field-tested in eight urological clinics in the German speaking part of Switzerland. The final version of the tutorial addresses several topics identified to be relevant in earlier studies. Users can either directly jump to a topic of interest or read the tutorial in a consecutive way. The different needs of information depth were met by additional information delivered in a glossary or by opening initially hidden information. The tutorial supports the treatment decision with a comparison of different options structured in different topics. To support the communication between physicians and patients the website offers a pre-structured digital notebook that uses questions to help patients identify topics to discuss at the next appointment. The field test of the tutorial in eight clinics showed promising results. The users are highly satisfied with the tutorial and their information needs are well covered.