Conduct is a potentially fair reason for Dismissal. Dismissals for Misconduct are probably the most frequent category of Unfair dismissal claim brought before the employment tribunal.

The conduct does not have to be of any particular character. It does not have to be 'reprehensible' or even 'culpable' for it to constitute a potentially fair reason, although the extent to which the claimant is blameworthy may be relevant when considering whether or not dismissal was a fair sanction in all the circumstances and also when assessing compensation, see: Appropriateness of dismissal: general below and Practice Note: The unfair dismissal Compensatory award—Contributory fault.

Dismissal for an isolated incident of misconduct will rarely be fair although, in some circumstances, the incident will be sufficiently serious to justify dismissal for a first offence. Generally, dismissal for misconduct will only be a reasonable sanction if the employee had committed earlier acts of misconduct and been warned that further incidents may lead to dismissal.