Mutual trust and confidence is a phrase used in English law, particularly with reference to contracts in UK labour law, to refer to the obligations owed in an employment relationship between the employer and the worker.
This concept relates to a new but highly important concept in employment law, and constitutes a term that is implied into all employment contracts. The implied term means that both the employer and employee should behave in such a way as to not undermine the employment relationship.
Academics now talk of the duty of good faith in the employment relationship. (i.e. both parties should "look out" for each other)
It is such an important issue that this implied term can override (in certain circumstances) an express term of the employment contract. e.g. excessive hours for junior doctors (See the Court of Appeal decision in Johnstone v. Bloomsbury Health Authority)