In this case study our aim was to gain more insight in the possibilities of qualitative formative peer assessment in a computer supported collaborative learning (CSCL) environment. An approach was chosen in which peer assessment was operationalised in assessment assignments and assessment tools that were embedded in the course material. The course concerned a higher education case-based virtual seminar, in which students were asked to conduct research and write a report in small multidisciplinary teams. The assessment assignments contained the discussion of assessment criteria, the assessment of a group report of a fellow group, and writing an assessment report. A list of feedback rules was one of the assessment tools. A qualitative oriented study was conducted, focussing on the attitude of students towards peer assessment and practical use of peer assessment assignments and tools. Results showed that students' attitude towards peer assessment was positive and that assessment assignments had added value. However, not all students fulfilled all assessment assignments. Recommendations for implementation of peer assessment in CSCL environments as well as suggestions for future research are discussed.Formative peer assessment in a CSCL environment 4 4Formative peer assessment in a CSCL environment: a case study Current educational practice in higher education stresses the development of lifelong learning skills. Among such lifelong learning skills is the ability to provide valuable feedback and suggestions for performance improvement to another person or a group. In spite of the apparent need to develop efficient and effective feedback skills, they are in general not explicitly included in most constructivist curriculae. One potentially valuable approach to train these skills is the use of peer assessment. We consider peer assessment as the process whereby groups of individuals rate their peers (Falchikov, 1995), or, more specifically, as an arrangement for learners and/or workers to consider and specify the level, value or quality of a product or performance of other equal-status learners and/or workers (Topping, 2003). In essence, peer assessment can be a specific form of collaborative learning and in the past decade collaborative learning has become a popular pedagogical approach in higher education (see Kirschner, Martens, & Strijbos, 2004).A course that includes peer assessment may contain multiple learning goals (Sluijsmans, 2002;Sluijsmans & Prins, 2004), and may thus have multiple beneficial effects. We label the improvement of content related performance as the first order learning goal and the acquisition of peer assessment skills as a higher order learning goal. Recently, many researchers have concluded that the implementation of peer assessment in the curriculum was beneficial for one or both levels of learning goals. For instance, Cutler and Price (1995), Freeman (1995), Horgan, Bol, and Hacker (1997), and Sluijsmans, Brand-Gruwel and Van Merriënboer (2002) report an increase in the quality of l...