The goal of this study was to analyse the role of the assessment of students with special educational needs from the perspective of professionals in Madrid (Spain), who work in multi-professional teams (psychologists, social workers, support teachers and others) and are responsible for its realisation, which, in principle, should be a support to move toward inclusive education. An interpretative phenomenological study was carried out, which gathered the opinions of 177 professionals of these multi-professional teams through 21 focus groups. The transcriptions were subjected to the thematic analysis method. The results show that the model and practices implemented in this region, regarding the usual assessment of these students, are generally seen as a barrier that needs to be addressed, since they facilitate the development of discriminating practices and decisions that reinforce and maintain an educational system of 'multiple ways', which is opposed to the right to inclusive education. These results are discussed, as well as the role that the assessment model should play in order to comply with this right. The study shows that the analysed evaluation is working as a barrier.