It depends. The general principle is that the requirements must be necessary for the safe and efficient performance of job-related tasks, because such requirements tend to disproportionately disadvantage women and members of some racial and ethnic groups. Statistics show that minimum height requirements adversely affect women, as well as members of some racial and ethnic groups, because those groups on average are shorter than men or members of other races or national origins. An employer therefore must show that the requirement is necessary for the safe and efficient performance of job-related tasks in order to justify a minimum height requirement. If there is a less restrictive way to accomplish the same goal other than a minimum height requirement, employers will be required to use that alternative to avoid liability for discrimination. For example, if a restaurant had a minimum height requirement for servers, presuming that shorter people generally cannot carry the required weight on a tray, a less restrictive alternative could be the requirement that all servers must be able to carry a set of minimum amount of weight on a tray. Of course, even if a restaurant or any other business implemented a minimum strength or lifting requirement, that requirement also must not have a significant adverse affect on a protected class of people unless required for the safe and efficient performance of job-related tasks. Weight requirements may be considered discriminatory because they often have an adverse impact on certain classes of people. In addition to problems with discrimination on the basis of sex or national origin, weight requirements also may constitute discrimination on the basis of disability. While weight-based disability claims have generally failed under the federal anti-discrimination law, the Americans with Disabilities Act, they have occasionally succeeded under the laws under certain states which either define disability differently or specifically make it illegal to discriminate on the basis of weight or personal appearance. It is also difficult to justify weight requirements as job-related if the purpose for the requirement is based primarily on physical appearance rather than the ability to perform a specific job-related task.