According to Acas1, the independent conciliation service, among the commonest reasons for dismissal are misconduct, inability to do the job and redundancy.
A dismissal will normally be ‘fair’ provided the employer has one of the five specified reasons (see below) for the dismissal and has acted ‘reasonably’ in carrying it out. When somebody is dismissed, they often say they will claim 'unfair' or 'wrongful' dismissal. The terms are often used interchangeably, particularly in media reports, but in fact they are entirely different and arise from very different concepts.