The neurological assessment of patients admitted to the intensive care unit after successful resuscitation from cardiopulmonary arrest may be difficult. We describe the cases of two patients who developed myoclonus within 24 hours of hypoxic respiratory and cardiac arrest. Initially, the clonic movements were thought to be generalised convulsions and were treated as such, until it became evident that the patients were aware and distressed. Posthypoxic myoclonus is a rare complication of successful cardiopulmonary resusitation. Recognition depends on the awareness that the syndrome exists, and is important so that correct therapy can be instituted. There may be important prognostic implications. Both our patients had normal intellectual recovery with moderate residual neurological disability from their movement disorder.