Neurological illnesses encompass a wide range of disorders, from headache to sensory, mental, speech and motor impairments. The causes may include trauma, vascular, tumour, infection, nutritional disorders, demyelination, neurodegeneration, inherited conditions and drug-induced syndromes. For most patients illnesses such as headache are readily amenable to treatment. However, since physiological repair mechanisms cannot replace neurones following cell degeneration and death, some neurological disorders are inevitably progressive and disabling.