One method for assessing teacher performance is the teacher portfolio. This is a collection of work produced by a teacher to highlight and demonstrate his or her knowledge and skills in teaching. A portfolio also provides a means for reflection and an opportunity to critique one's own work and evaluate one's own effectiveness as a teacher. Rather than being a folder laden with teaching artifacts and evaluations, a teacher portfolio should be a document created by a teacher that indicates the teacher's duties, expertise, and growth in teaching. Each assertion in the portfolio is documented in an appendix or a reference to outside material. Portfolios are used as a means of authentic assessment in evaluating the teacher for licensure or employment decisions, and they are also a way to provide feedback to teachers so that they can improve their teaching. Portfolios that are used to make personnel decisions come under a higher level of scrutiny than if the purpose is professional growth alone. Making the portfolio evaluation as objective as possible requires careful planning. Steps for implementing a portfolio program are outlined. Four sources are listed as recommended reading. (Contains 1 figure.) (SLD)