On a warm, May afternoon, Karen, the high school biology teacher, perched on a stool in the lab reviewing her portfolio. Five years ago her school district had decided to experiment with replacing the annual teacher evaluation by an administrator’s classroom visit with a one-on-one conference based on the teacher’s portfolio. During the first year of the experiment, all teacher evaluation had been suspended as the faculty, working alone, in grade level groups, in subject area groups and as a body of the whole, struggled to reach agreement on questions about portfolio development. The first question was, “Evidence of what?” Other questions were: what documents would provide this evidence; how many documents; what types of documents; and what would be done with the portfolio once it was developed. During the second year, all of the faculty members were busy collecting the documents to provide the evidence for their first portfolios. There had been many conversations among the science teachers about whether this lab was the right one to videotape to display a commitment to student-centered lab work or whether that test really captured ongoing student evaluation. Deeper collegial relationships began to develop as the faculty, focusing on portfolio development, shared their successes and concerns. The faculty wanted this experiment on teacher evaluation to work because the judgment about the quality of teaching would reside among the teachers. The process of portfolio development had become formalized in a very short time. Karen kept a file drawer of potential documents for evidence-lesson plans, tests, videotapes, student work samples. Attached to each document was a caption. In September she had identified her professional goals for the year and had rehearsed them as she collected and tagged documents. Last week she had assembled the documents that demonstrated her progress toward her goals and arranged them as evidence to tell her story. Yesterday she had met with the other science teachers on the faculty and discussed her portfolio presentation. Now she was reviewing the documents to be submitted in the portfolio. Her chair was writing a letter of attestation to include in the portfolio, which she would deliver to the principal on Friday afternoon. On Monday she and the principal would meet and discuss her portfolio, her ideas for next year’s goals, and her decision to advance to the rank of Master Teacher after next year.