As with any legally binding contract if one of the parties acts in a way that breaks the agreement they may be liable to have action taken against them in a court or tribunal.
However actions for breach of contract have some restrictions when used in most employment situations.
The main restriction is that Employment Tribunals cannot deal with claims for breach of contract where the Claimant is still employed - claims can only be made by ex-employees.
However where there are breaches of contractual working terms and conditions they will often also infringe statutory rights on protection of wages or working time which are claims that can be made in Employment Tribunal.
Where breach of contract claims are made by ex-employees there is a limit of £25,000 on the value of the claim that can be made to an Employment Tribunal. Care has to be taken as well because an employer can make a counterclaim for any breach of contract by the employee.
Claims for breach of contract can also be made to the County Court where the above restrictions do not apply.
If the breach of contract by the employer is very serious then it may entitle the employee to resign and claim constructive dismissal.
A dismissal that is committed in breach of contract (most commonly where insufficient notice is given) is called a wrongful dismissal and may give an employee a right to claim some compensation such as payment for the full notice period.