It is proposed that assessment of a worker who performs manual labor must include specific tests of physical capability. Such tests must meet certain criteria to be accepted as medically, economically and legally justified. The medical and economic justification for such tests is recognized by all concerned with controlling the excessive costs and human suffering associated with over-exertion strain/sprain injury and illness in industry. The legal basis for such tests is not well established and will not exist until a documented history of success or failure is developed in the courts for different types of tests. It is hoped that as various tests are developed by medical departments the criteria stated in the first part of this article will be of assistance. As to the status of isometric strength testing for employee selection and placement, it is being implemented as part of the medical examination in a number of large industries as an experimental medical procedure. Data are being continually gathered to further validate and refine the procedures. It is discussed in this contest as one of several methods which needs to be considered and evaluated to reduce musculoskeletal injury and illness in industry.