*Assessing impairment in major life activities--not simply the presence of symptoms--is critical to psychiatric/psychological diagnosis. Grounded in 16 years of research, this the first empirically based scale of its kind. *Barkley is a successful, visible, and respected researcher and clinician. *Easy to administer and score, the assessment is accessible to a wide range of professionals, with photocopy rights granted to users. *Both a Quick Screen and a long form are included, normed on adults from ages 18 to 89. *Other available scales rely on clinical judgment and lack the validity and reliability of the BFIS.