Description: In the literature, portfolio is viewed as promoting meaningful and authentic assessment in relevant contexts (e.g., Allal, Wegmuller, Bonaiti-Dugerdil & Cochet Kaeser, 1998) and thereby constitutes an "alternative" practice to traditional assessments. It is for this purpose that a portfolio was implemented in the field of special needs at the University of Education of Lausanne (Hoefflin & Allal, 2004). The paper will focus on the different forms of feedback and regulation tied to a portfolio. In English-language literature on formative assessment, feedback is conceptualized as a crucial factor in portfolio practice (e.g., Tillema & Smith, 2000). As for the French-language publications, they stress the important role of regulation, including feedback and adaptation of instruction (Allal & Mottier Lopez, 2005). Distinctions are notably made between three modalities of regulation associated with formative assessment: interactive regulation, retroactive regulation, proactive regulation (Allal, 1988). In a situated learning perspective, we argue that both individual and social processes contribute to the regulation of learning, in a dialectical relationship (Allal, in press; Mottier Lopez, 2005). Our research will concern a training module about communication and language disorder. It is composed of two courses of 24 periods (2 ETCS), and of a seminar of 12 periods (1 ETCS). Different feedback is given to the student-teachers, in particular: (a) At the start of the first course, the student-teachers were each asked to assess their current knowledge through a written interview about their know-how in the field of children with learning disabilities (LDS) and poly-handicapped children. A written and collective overview is then proposed by a first supervisor, whose purpose is to regulate future teaching and learning processes; (b) Following the second course, an individual written feedback is proposed by a second supervisor on the basis of students' portfolios. A proactive regulation is expected on the pedagogical practices of the student-teachers; (c) Small-group interactions, including both supervisors, take place at the end of the final seminar. Its purpose is to incite the student-teachers to assess their progress during the training module. Our research questions are: What are the components of supervisors' feedback, according to its different social format (collective, individual, small-group interactions) and according to its temporal insertion in the training module? What are the expected regulations? What are the students' perceptions of feedback and regulations tied to their portfolios? Methodology: Two supervisors and 50 student-teachers are implicated. Three methods are used: - Qualitative analyses of the different feedback strategies, in the form of written traces and transcriptions of social interactions; - A questionnaire filled in by the student-teachers at the end of the module. The questionnaire (using a five-point Likert scale) is about the students' perceptions of the portfolio assessment; - A final individual interview with both supervisors. A strategy of triangulation of data is planned, in order to investigate the feedback components and the resulting regulations from the actors' viewpoint. Conclusions: Our findings aim at contributing to the study of regulations which are instrumented by a portfolio (Mottier Lopez & Wegmuller, 2005). The literature devotes very little attention to this aspect, stressing more the different types of portfolio, their construction and implementation (Tillema & Smith, 2000). However, the regulation, including feedback, is an essential issue in order to investigate the effectiveness of the portfolio use, as a possible "alternative" practice of assessment. Advantages and limits of the different forms of feedback that are studied in our research will be discussed, so as to sketch some practical implications.