ABSTRACT
Mood swings are part of life. Everyone experiences highs and lows, mostly in response to life events. Many people reading this chapter will have experienced persistent low mood and will have fi rst-hand experience of how mood infl uences ideas and feelings about past, present and future life. Other readers (like this author) may also have experienced persistent high moods, for which they may have been hospitalised and for which they may take long-term medication. Additionally, in a book for mental health professionals, almost all readers will have experience of working with people who have had, or who are in, extreme moods.
