The Swedish school system comprises: (1) Pre-primary school (Forskola), typical age 1-5; (2) Preschool class in the compulsory school (Grundskola) typical age 6 (participation voluntary); (3) Compulsory school, typical age 7-16, grades 1-9, and (4) Upper secondary school, 17 programmes (4 mainly academic, 13 vocational), typical age 16-19, grades 10-12. Pupils at compulsory school in Sweden are not only assessed through grades. In the 1980s pupil performance reviews involving pupils and parents were introduced to provide information on how pupils are performing in different subjects. In 2005 this system was strengthened through the introduction of individual development plans that are to describe the pupil's strengths and weaknesses and the schools' efforts to provide support for the pupil. A national testing system is used to support assessment by teachers; this comprises compulsory national tests, voluntary diagnostic material and testing material in an Internet-based test bank. This paper discusses the objectives, organization, and use of results of the national testing of pupils in Sweden. This paper contains the following parts: (1) General Overview of Pupil Assessment; (2) Historical Background to National Testing and its Political Framework; (3) Aims and Organizations of National Testing; and (4) Impact of National Testing.