Insomnia is a very common and easily treated condition. It may be the prese
nting symptom of many other medical conditions and usually is not a sign of
psychological or psychiatric illness. Untreated, in somnia can cause signi
ficant economic hardship, morbidity, and mortality, and it may be a risk fa
ctor for development of depression or anxiety. Actigraphy and sleep logs ar
e essential tools in evaluating insomnia. Their use usually results in a sp
ecific causal diagnosis, with effective therapeutic implications. Treatment
includes both pharmacologic and behavioral interventions.