Employment-at-will is the concept that EMPLOYMENT is a CONTRACT between an employer and an employee and therefore subject only to the terms of the agreement between the two. As such, workers are hired for an indefinite duration, and either the employee or the employer may end the relationship for any reason and at any time. Implicit in employment-at-will is the idea that government does not determine employment relationships. The concept of employment-at-will evolved out of the AMERICAN INDUSTRIAL REVOLUTION as workers and employers shifted from small-scale, local craft guilds to an industrial system employing hundreds and thousands of workers. Employment-at-will became part of American COMMON LAW based on rulings in the 1870s and 1880s. Most discussion of employment-at-will focuses on an employer�s right to terminate a worker without having to justify the action. Contracts, union agreements, and federal discrimination laws limit the right of employers to terminate employees. Until the WAGNER ACT of 1935, UNIONs had relatively little power. Union strikers were often prosecuted under criminal conspiracy laws. The Wagner Act gave union members the right to COLLECTIVE BARGAINING and through these contracts; workers often gained protection from being fired, except for JUST CAUSE. Law Professor Jane Mallor and her coauthors note that public employees are also often protected from termination without just cause. In what is called the public-policy exception, recognized by about 80 percent of the states, terminated public employees can claim WRONGFUL DISCHARGE based on �(1) refusal to commit an unlawful act, (2) performance of an important public obligation (jury duty or whistle-blowing), (3) exercise of a legal right or privilege (e.g., making a WORKERS� COMPENSATION claim or refusing top take an illegal polygraph test).� Other limitations on employment-at-will relationships are based on federal antidiscrimination laws. Generally workers are protected against termination based on personal traits, age, and disabilities. In some states, promises by employers and implied good faith and fairdealing covenants also limit employment-at-will. But as Cynthia Fisher, Lyle Schoefeldt, and James Shaw summarize, � . . . between 70 and 75 percent of employees in the United States have no such explicit protection.�