This chapter focuses on the empirical methods for gathering information about real users. From among the wealth of usability research methods, Jakob Nielsen advocates for one empirical method -namely, usability testing. According to him, it is the most fundamental usability method, as it gives direct information about the way in which people use computers and the problems they encounter. During a usability test, participants can be asked to think aloud while performing tasks: Thinking Aloud Protocol (TAP) is a popular data-collection method in the usability community. It is also a widely used traditional method in translation process research. Thinking aloud reveals user's mental models and problems related to the product. Eyetracking is a method for observing the user's eye movements in order to analyze interfaces, to measure usability and find out about human performance. The user's eye movements are recorded and then analyzed. This chapter has concentrated on actual users and contexts of use.