By definition (Merriam-Webster, 2003) a group is “a number of individuals who have some unifying relationship.” In the design world, we consider a user group to be a group of people who use or will use some product, such as a smartphone, software application (e.g., Microsoft Word), or a service, such as an exercise program provided at a local senior center. User involvement in design is an essential component of the user-centered design approach. A lack of attention to user needs and preferences can lead to a lack of adoption or abandonment of a product, errors, inefficient use of a product, and user dissatisfaction. For example, the IBM PC Jr. was designed in the 1980s to be used in the home. However, the product turned out to be a commercial failure and was actually pulled from the market due to a number of design and implementation problems. One problem was the small “chiclet” keyboard, which was difficult to use for extended keying, such as word processing. This design flaw caused frustration and dissatisfaction as users expected that they would be able to use the PC Jr. at home for this type of activity (Sanger, 1984). There were also problems with the amount of memory storage, which was insufficient for some of the desired applications. Generally, design problems such as these can be avoided if user needs, abilities, and preferences are accounted for during the design process.