Among the challenges clinicians and researchers face regarding behavioral disturbances of dementia are how to conceptualize them and how to measure them. The Diagnostic and Statistical Manual of Mental Disorders (4th ed.) recognizes that dementia can be associated with mood symptoms and delusions by formally coding for them but does not have codes for coexisting hallucinations or other specific behavioral symptoms associated with dementia. One reason for this lack of coding classification is the difficulty in conceptualizing the many behavioral disorders, symptoms, and problems seen in patients with dementia.