The first purpose of this thesis was to examine whether sensorimotor therapy utilizing the training program ”Retraining for Balance” might be an appropriate technique for sensorimotor proficiency. The second purpose was to gain increased understanding of the effects of sensorimotor therapy on the physical and psychological development of children and youth. A third purpose was to put sensorimotor therapy in a wider perspective through a somewhat novel extension of the theoretical framework. Two naturalistic studies were conducted. Paper I was quantitative and comprised 232 children (181 boys and 51 girls) divided into three groups (1) a younger group (7 years or younger, n=65), (2) a middle group (8 to 10 years old, n=91) and, (3) an older group (11 years old or older, n=76). The participants presented attentional and motor difficulties before starting therapy. The treatment period was in average close to 3 years. Results indicated significant improvements concerning sensorimotor skills in all age groups. Paper II was a qualitative study, which included the records of 8 children (7 boys and 1 girl) randomly selected from the cohort of 232 children. The analysis used the EPP-method and yielded 3 overarching themes, which together formed “the kinesthetic-vestibular developmental model”. The model illustrated how Introductions of sensorimotor exercises pushed the therapy process forward due to periods of Regression and Transformation. The results were generalized to the remaining 224 children in the cohort by comparing each participant’s records with “the kinesthetic-vestibular developmental model”. The tentative conclusion was that sensorimotor therapy according to the method “Retraining for Balance” might constitute a complement to treatment of ADHD, DCD and LD but controlled studies are necessary before more decisive conclusions can be drawn. / Baksidestext   This thesis had three purposes. (1) to examine whether sensorimotor therapy (SMT) using the training program ”Retraining for Balance” might be a proper technique for sensorimotor proficiency. (2) to gain increased understanding of the effects of SMT on physical and psychological development and, (3) to put SMT in a wider perspective by an extension of the theoretical framework. Two naturalistic studies were conducted. Paper I, which was quantitative, comprised 232 children who presented attentional and motor difficulties. The cohort was divided into three groups depending on age and results after therapy indicated improvements in all groups. Paper II, a qualitative study, selected records of 8 children from the cohort. Analysis yielded 3 overarching themes, which together formed “the kinesthetic-vestibular developmental model” illustrating how Introductions of exercises pushed the process forward due to Regressions and Transformations. The results were generalized to the remaining 224 children. The tentative conclusion of this thesis was that SMT might constitute a complement to treatment of ADHD, DCD and LD but controlled studies are necessary before decisive conclusions can be drawn.