Editor's message: The contract of employment forms the backbone of the employment relationship. There is no obligation on employers to put contracts in writing (although certain key employment terms must be set out in a written statement of employment particulars). However, oral or ambiguous terms have the potential to lead to disputes - so it is advisable to make sure your terms are clearly set out in writing, so that everyone understands what has been agreed.
While express contractual terms are those agreed between the organisation and the employee - or incorporated from, for example, a collective agreement or a staff handbook - terms may also be implied into the contract. Often this will be by custom or practice, or the parties' conduct, or because of what a court or tribunal deems must have been intended when the two parties entered into the contract.
One of the most important implied terms is the implied duty of mutual trust and confidence - employees claiming that they have been constructively dismissed often cite a breach of this implied term.
Zuraida Curtis, senior legal editor, employment law and compliance
HR and legal information and guidance relating to contracts of employment.