In Sweden, an increasing number of pupils are defined as having some form of difficulties in school. In order to receive special support measures in school, these difficulties must have been subject to a pedagogical examination that state that the pupil is in need of special support measures. This work of identifying and defining difficulties implies that questions about normality and deviance inevitably come into play in school. There has been an increasing demand in school politics to identify these difficulties as early as possible, and this demand has placed further pressure on school personnel in this issue. Furthermore, the personnel’s perspective on the difficulties is also important, i.e., in terms of their origin, because this has importance for the design and content of the special support measures. The overall aim of this thesis is to analyse the tension between normality and deviance that is manifested in the school’s work procedures for pupils with special educational needs. Related to the overall aim, four overarching research questions are addressed. How have pupils with special educational needs and special education been articulated in national policy documents during recent decades? What perspective on school difficulties are being portrayed in schools’ individual educational plans for pupils with special educational needs? How do school personnel identify and differentiate pupils with special educational needs from “normal” pupils? How do pupils with special educational needs and their parents experience the special support measures that they receive in school and what seems to be the main concern of such support measures? The thesis consists of four studies that are based on different empirical materials such as policy documents, individual educational plans (IEPs) and qualitative interviews with school personnel, pupils and parents. The methods that are used for analysing the material are policy analysis, content analysis and grounded theory. The results show that the target group for special support measures has been ascribed with different meanings (over time) in policy documents, something that has affected the recommendations of the support measures and the choice of actors who are assigned to provide such support. Furthermore, the IEPs, as well as the interviews, reveal that an individual perspective on school difficulties seems to be deeply rooted in school.  The identification process of special educational needs followed three models: a pedagogical model, a social model, and a medical/health model.  However, the process of sorting out and defining these pupils invoked ambivalent feelings in the school personnel and the school class usually became the frame of reference for normal or deviant behaviour. Finally, the pupils’ and parent’ main concern of special support measures in school were described as a struggle for recognition and inclusion. The results are discussed with theoretical perspectives on school difficulties and special education. In the concluding discussion, it is argued that pupils with special educational needs have to balance between normality and deviance in school, but also between a pedagogical and a medical discourse by means of having a medical diagnosis in school.