Gross misconduct is conduct by an employee that is so serious that it goes to the root of the employment contract and effectively destroys it.

Gross misconduct covers actions like theft, assault on another employee, fraud, bullying or harassment.

Where an employee has been involved in an act of gross misconduct, the employer is entitled to summarily dismiss them, i.e. to dismiss them without notice. A fair procedure involving consultation will usually have to be followed in order to avoid a finding of unfair dismissal, however.

It can sometimes be hard to assess whether misconduct is serious enough to amount to gross misconduct, or whether it should warrant a warning of some sort. If a warning, the terms of the warning will need to be considered carefully so as to help rather than hinder any future disciplinary process.

Further resources on unfair dismissal can be found here.