Method

Usability walkthrough is a category for methods relying on the judgment of evaluators to determine the ease of use of a user interface. During the walkthrough, a combination of HCI evaluators, users, and developers seek out usability problems and recommend solutions.  In the HCI discipline, this technique is known as "heuristic evaluation".  These 10 usability principles (.pdf) lend structure to an evaluation.  Usage scenarios are useful when conducting a usability walkthrough, but they are not required.

Results

A list of usability issues defined by the general rules of user interface design, or a lack of compatibility between the user interface and the system's anticipated usage.  See also a brief heuristic case study of a remote printing dialog box and an evaluation conducted to accompany a research proposal for a telecom broker website (.pdf). 

Timeframe

Two-four days to walk through the system, 2-3 days to document the results.

Preparations

If there is only one HCI evaluator, then one representation of the user interface is required. If a larger number of evaluators are employed, multiple printouts or a projected UI are necessary, along with a conference room. Usage scenarios are helpful for "walking through" the sequence of actions that the users are expected to take when the system is in actual use.

Additional Reading

Usability Inspection Methods. Jacob Nielsen, 1994.