This thesis describes the research and design done to develop a new method of online product comparison. The method is a proposed improvement over current product comparison websites. Well known Dutch examples of these are Beslist.nl and Kieskeurig.nl, which compare many different products, from TV’s to baby strollers. This sort of product comparison websites are currently much used on the internet. They offer functionality to compare products and the prices for which these products are offered at different online stores. However, these websites are not without their problems. Based on the analysis of academic literature, current solutions and user opinions, the following issues have been determined. The product comparison websites currently focus on comparing and listing as much as possible products and their specifications. The result of this is that the user is presented too much choice, creating an information and choice overload for the user. This complicates the decision making process for the user and can result in a low decision certainty and decision satisfaction. Furthermore, the current solutions are not based on supporting the user in his or her decision making process. Also, the current solutions do not offer personal product recommendations. Based on this analysis, a focus for a new design has been created. The key point of this focus is that the new design should be much more user-focused compared to current solutions. The most important goals within this focus are to support the user in his decision making process and to reduce information and choice overload. Also, the design needs to use personal input from the user, and react on it. Based on this focus, several ideas have been generated. These ideas have been made to multiple prototypes and have been evaluated by users. Based on this evaluation, one idea was found to match the focus the best. This idea has been further developed into a detailed concept. This concept uses the principal of multi-dimensional similarity scaling, a proven statistical method, to determine the amount of similarity between different products. This similarity between products is used in the design to recommend products to the user. The design asks users to choose one out of three products, which have significant differences between them. This is a relatively simple choice. Based on the user’s choice, the design suggests two new products, which are more similar to the previously chosen product. Then again, the user can make a choice between three products. With every choice, the products that are recommended become more similar and their specifications become more detailed. In the process, the design determines the preferences of the user, based on his product choices. This process of making a choice between three options is repeated until the user has made a final product decision. This concept has been made to a fully interactive prototype and has been evaluated by users. User could compare and choose between a range of coffee machines. From these qualitative tests, positive results have been found. Users could make a product choice with high decision certainty, without experiencing much information or choice overload. Their decision satisfaction was also high. Compared to the current solutions, the users stated that the concept has both a higher usability and that it is more useful to compare products and make a final decision. The most positive points that the users named were the good overview that the concept provided and the simplicity in which they could compare products with it. Finally an analysis has been done to find the most suitable product categories to implement be compared with the new system. These were found to be household appliances (e.g. coffee machines, washing machines), consumer electronics (TV’s, mobile phones, music players) and computer hardware (laptops, tablets, computer parts). These categories combined created an online revenue of around 2.2 billion in 2010 in the Netherlands and are promising categories for market implementation. Based on the positive evaluation of the concept by both users and commercial parties, the graduating student has chosen to continue with the implementation of the design. He is currently involved with a group of people to create a new company and to start a new, user-focused, product comparison website. On this website, the goal is to implement much of the design presented here. He is looking very much forward to do so.