Work-to-rule refers to a specific type of industrial action whereby workers deliberately adhere to their contractual obligations as a way of protesting against their employer's policies. There are several synonyms for work-to-rule, including "strict adherence," "rigid compliance," "letter of the law," and "formalistic approach." These terms all describe the same basic idea: workers are following rules and regulations to the letter, with the aim of slowing down or impeding the production process. Work-to-rule can be an effective way for employees to express their discontent, as it puts pressure on management to address their concerns. However, it can also result in decreased productivity and frustration for both workers and their employers.