Imaging evaluation of the patient with a non-palpable testis has evolved over recent decades. The rational explanation of imaging in these patients requires a clear understanding of the various causes of a non-palpable testis, and an appreciation of the utility and limitations of the available imaging modalities. This review describes the classification of non-palpable testis and discusses the role of modern imaging in evaluation. In particular, the relative accuracies of ultrasound, CT and MRI is reviewed.