The main purpose of this paper is to outline a possible reductive explanation of emotion in neurophysiological terms. But it will also be argued that such a reductive explanation is more difficult to achieve than is commonly thought, in that it has to address conscious emotional experience. It will be argued that when an emotion is conscious, what makes it the emotion it is, and an emotion at all, is its phenomenal character, and when an emotion is unconscious, what makes it the emotion it is, and an emotion at all, is the phenomenal character it would have if it were conscious. This has the consequence that the theory of emotion cannot be insulated from the theory of consciousness, and a reductive explanation of emotion must target the phenomenal character of conscious emotional experiences. A possible reductive explanation of this sort will be outlined.