Insomnia is often a secondary problem to other disorders, i.e. physical ailments and psychiatric conditions. In some cases insomnia is the main symptom where the individual's worry about not sleeping contributes to the problem. Lack of sleep may causes a decrease in general functioning and health.
Therapy is based on a joint plan which may include keeping a log book which could monitor one's activities, feelings and thoughts around bedtime. Environmental factors play an important role in insomnia. Worries can be addressed and put into perspective or problem solved during therapy. Relaxation techniques may help with physical arousal problems.
Overcoming insomnia: a CBT workbook (Edinger & Carney)
Relief from insomnia (Morin)
Say good night to insomnia: the six week, drug free programme (Jacobs)
Goodnight Mind (Carney and Manber)