An investigation was made of 1,448 interstate bus drivers to determine the effects of whole body vibration exposure on these individuals. Chi square tests of the prevalence of specific chronic conditions in the study group and two comparison groups showed a number of significant differences in their morbidity experience. Evidence seems to implicate whole body vibration as a factor in the development of certain occupational diseases of interstate bus drivers among which are a number of venous, bowel, respiratory, muscular and back disorders. The combined effects of body posture, dietary habits, and whole body vibration cannot be ruled out for such disorders as varicose veins, varicocele, hemorrhoids, diverticulosis, appendicitis, and inguinal hernia. Body position, postural fatigue, and whole body vibration may all be operative in the development of spine and supporting structure disorders such as displacement of intervertebral disc, ankylosis of the spine, and vertebrogenic pain syndrome.