In this case series, we describe four children and adolescents with tall stature or growth acceleration to illustrate the diagnostic evaluation of tall stature according to the new Paediatric Association of the Netherlands (NVK) Guideline on growth disorders. A 14-year-old girl with tall stature and a relatively late onset of puberty was diagnosed with idiopathic familial tall stature, and the patient decided not to opt for epiphysiodesis. A 14-year-old boy with prepubertal growth acceleration and a history of behavioural problems was diagnosed with Klinefelter syndrome. A 7-year-old boy with tall stature, arachnodactyly, pectus excavatum and lumbar scoliosis was diagnosed with Marfan syndrome. Finally, a 16-year-old girl with isolated progressive tall stature was diagnosed with growth hormone excess caused by a pituitary somatotroph adenoma. The most clinically relevant conditions associated with tall stature are Klinefelter and Marfan syndrome, and secondary growth disorders such as precocious puberty and growth hormone excess.