Informal caregiving contributes significantly to the health and well being  of chronically ill persons. While a vast literature demonstrates this connection, the cost and financial burden of informal caregiving has received considerably less research attention, especially as it pertains to bipolar disorder. Aims of the Study: This paper develops an integrated burden model of informal caregiving, which is contrasted with other more traditional models of caregiving costs, and then uses these models to estimate the financial burden of bipolar disorder.  The "goodness" of these various models is measured in terms of their correlation with measures of objective and subjective burden for caregivers of persons with bipolar disorder.