In this work, we examine the neuroradiologic features of the main non vascular clinical conditions responsible for secondary headache; excluding CSF hypotension, which will be treated extensively in another work in this supplement. Headache is not a constant feature of intracranial mass lesions, even of large extension. Headache has a high diagnostic value in children, as it can be the only heralding symptom, sometimes even for a long time, of severe intracranial pathologies, which later give rise to seizure or focal neurological signs. Particular attention should be paid to children affected by leukaemia under pharmacological treatment, in which headache is almost always the presenting symptom of serious neurological syndromes, consequent to antiblastic drugs.