Functional assessment—the measurement of an individual's ability to perforni daily life activities despite disease, disorder, or impairment-is becoming a vital supplement to traditional clinical assessment batteries in rehabilitation. From a clinical perspective, functional assessment seems to bridge the gap between identifying specific behaviours, and evaluating how those behaviours affect an individual's ability to function in natural contexts (Holland 1980; Sarno 1983; Beukelman et al., 1984; Aten 1986; Frattali and Lynch 1989; Hartley 1990; Kao 1990). From a public policy perspective, functional assessment takes on added import, providing the means to set reimbursement rates, determine eligibility for services, and measure the quality of long-tern1 or rehabilitative care (Hosek et al., 1986; Kane 1987; Health Care Financing Administration 1989; Cornelius 1990).