Past performance is a good indicator of future performance, which is why performance-based interviewing occurs. In the performance-based interview, a candidate is given an assignment to perform a task, which is then evaluated by the interviewer. A sampling of tasks might include:
In sales: sell me this pen.
In media: write sample copy.
In training: make a presentation.
In IT: tell me how to improve my firm's website.
This is a test where the employer can gauge how well the candidate designs an ad, delivers a sales presentation, analyzes a report, and so forth, to discover how he will perform on the job.