Some contracts of employment contain a variation clause that can allow your employer to make changes to your contract. Employers should only use these clauses to vary a contract if they have a good reason, for example the business is struggling financially and needs to cut staff hours. Imposing changes of contract. If an employer imposes changes upon an employee the employee is forced into deciding what action to take. An employee must respond quickly where the employer tries to impose contract changes unilaterally; otherwise he or she may be taken to have agreed the change by continuing to work (see above). Changing contracts of employment: nine key considerations for employers By Clio Springer on 3 Nov 2015 in Trade unions , Employment contracts Contracts of employment cannot be changed unless both parties – the employer and the employee – agree.