For several years, Western University Libraries has had a varied instruction program that includes independent credit courses, courses linked to one or more discipline courses, and customized bibliographic instruction sessions. The librarians who deliver instruction are considering different methods of assessment. This article focuses on the use of course portfolios in a medium-sized academic library. Two course portfolios are described: one for a 100-level library course and the other a 300-level library course, both of which were linked with discipline courses and offered for one credit. Library literature thus far has focused on instruction program or teaching portfolios, not on the use of portfolios to assess a specific course. This article discusses the philosophy and format of the course portfolio and the use of the portfolio for self-assessment, and for evaluation and revision of these two courses.