The first of a two-volume report on motor vehicle driving by handicapped persons focuses on driving behavior for 19 types of handicapping conditions. Information is detailed regarding driver education and assessment materials, present state laws regarding licensing, relevant medical opinion regarding licensing and examination, complicating factors (such as the use of therapeutic drugs), and private and commercial driving behavior for specific conditions, including the following: mental retardation, mental illness, neurologic and cerebrovascular handicaps, epilepsy, diabetes, musculoskeletal handicaps, hearing disorders, thyroid disease, renal disorders, cancer, and obesity. Automotive adaptive equipment is briefly considered. Among 12 recommendations made are for a more comprehensive analysis of the driving task for normal drivers, a large scale epidemiological study to measure the accident and violation rates of specific handicapped groups, and validated assessment and evaluation procedures. (CL)