Invariably, proponents of performance assessment also advocate the use of student portfolios. In doing so, they also remind us that a portfolio is more than a folder stuffed with student papers, video tapes, progress reports, or related materials. It must be a purposeful collection of student work that tells the story of a student’s efforts, progress, or achievement in a given area over a period of time. If it is to be useful, specific design criteria also must be used to create and maintain a portfolio system.