GOMS analysis applies to situations in which users perform tasks they’ve previously mastered. In the psychology literature this is called having a cognitive skill, i.e., users are not problem solving, not hunting around for what they need to do next. They know what to do and all they have to do is act.

GOMS has been shown to work well in user-paced, passive systems. For instance, there are many single-user applications where the user tells the system what to do, then the system does it and tells the user what it has done. GOMS has been applied to applications such as text and graphics editors, page layout, spreadsheets, information browsers, operating systems, ergonomic design systems, CAD systems, and WWW pages.

GOMS has also been shown to be valid in single-user, active systems, where the system changes in unexpected ways. There are GOMS models, of radar monitoring and of video games, where the system throws new situations at the user at a maniacal pace. The knowledge gathered by a GOMS analysis is sufficient to predict what a person will do in these seemingly unpredictable situations.

GOMS can also describe the behavior of “surrogate users”. The catalogue-sales situation is one example of a surrogate user. The user of the interface is the employee on the telephone trying to help customers, but the overall task is really defined by the customer’s needs.