Usability testing involves observation and assessment of representative users interacting with a prototype or product. Users may be tested one at a time—or in pairs (to generate conversation as the users work together to operate the device or application). The test environment is typically a standard conference room, with space for the users, observers, and audio-visual recording equipment to provide a record for subsequent analysis. Users in the test are provided with directions for the tasks they are requested to complete and support materials that are expected to be available to users in the field (e.g., an instruction manual).

Information collected in a usability test includes whether or not a user successfully completed a task, details about the actions taken by the user while attempting to complete a task, verbal comments from users during tasks, and feedback from users in post-test interviews.

It is often valuable to continue usability assessments in the field, when a new device or application is introduced in a trial for a small group of users. Such assessments can be used to determine if a device that has been demonstrated to be usable in a special test environment will be used as expected in the field.