Lesions of the anterior part of the frontal lobe can cause disturbances of micturition, and more rarely, of defaecation. It is already known that lesions of the paracentral lobule can cause retention of urine and faeces, and the paracentral lobule is in fact a part of the frontal lobe. But the lesions which I will talk to you about are situated in the anterior half of the frontal lobe. To illustrate this subject, I will talk to you about four groups of cases; they are cases of intracranial tumours, of aneurysms, of brain wounds, and of leucotomies. I will start with a case of an intracranial tumour. This was a 57 year old man who was sent up to hospital as a case of epilepsy of late onset. He had become increasingly sleepy and rather bad-tempered over the previous few months. His wife said that during the previous year he had changed from being a pleasant man to a nasty man. He had become more irritable and at the same time he took life less seriously. He had started making silly mistakes in his work as an accountant; and he himself had noticed that his mental processes had begun slowing up. When he was questioned, he told me that for several months, as soon as he felt the need to micturate, he would have to rush. In fact, he would actually have to run; for he was quite unable to stop urine passing once the urge to micturate became severe. Over the same period he had become constipated. His wife told me that when they went out, she would have to plan their journey to pass near lavatories, so that he could go to them during their walk. The history and the lack of physical signs, except for diminished movement of the left side of his face and diminished left abdominal reflexes suggested a frontal tumour, probably on the right side. Radiological examination showed a large right frontal parasagittal meningioma, situated mainly in front of the coronal suture. Mr. McKissock operated and removed the entire tumour. Three days after the operation, the patient told me that he was afraid to go to sleep, as when asleep, he wet the bed. He was also being incontinent of urine when awake.