Disabled persons cannot be identified with precision. Because of this, there can be no single unambiguous count of disabled persons. However, the Social Security Administration surveys indicated that in 1966 and 1978, about 17 percent of the population considered themselves as having some degree of work disability. Severe work disability increased from 6 percent in 1966 to 8.6 percent in 1978. In 1966, 19.2 percent of the severely disabled reported being in the labor force; in 1978, this proportion had decreased to 13.6 percent. The U.S. disability system consists of a social security track, complete with medical care and limited rehabilitation services; a public assistance track, also with medical care and rehabilitation services; a work injury track; special tracks for veterans; and a private sector track. Laws that alter minimum standards of employment, that set aside money or jobs, and that attempt to guarantee employment also characterize the system. Rising disability benefit rates lower labor force participation rates. Studies indicate that the vocational rehabilitation program has an impact on some clients, but studies need to be extended. The United States has developed a costly and reasonably adequate system of income benefits for the disabled. It is time to give more thought to the adequacy of rehabilitation efforts, with the full realization that rehabilitation, like any complex social goal, cannot simply be mandated into existence. (78 references) (CML)