In this clinical case, the importance of early detection of Hurler syndrome for outcomes of stem cell transplantation in this patient population is illustrated. Nowadays, children with Hurler syndrome can be treated with stem cell transplantation, but the results largely depend on the moment of treatment. If the procedure is initiated in an early stage of disease, better results can be obtained. Therefore, early recognition of the disease is essential. In this study, the presenting symptoms of fifteen Dutch patients were studied. The median age of diagnosis was 10 months, but by timely recognition of typical facial features, macrocephaly, hepatosplenomegaly, and kyphosis all patients might have been diagnosed four months earlier on average.