Australian law prevents unfair dismissal from employment. An employer cannot fire an employee without a valid reason such as poor performance after additional training. Being sick, reporting unsafe work conditions, union membership or legal proceedings are not valid reasons. Employers must provide notice periods ranging from 1-4 weeks depending on tenure or pay in lieu. Valid reasons for dismissal include misconduct, health and safety risks, theft, assault or not following reasonable instructions. Not all workers are protected from unfair dismissal such as casuals or those within probation periods.