This case in the High Court reinforces the principle that post-employment restrictions must protect a legitimate interest of the employer to be effective. This can include preventing poaching of customers or staff, and protecting confidential information. Even then, it is only likely to be enforceable if it drafted in a way that is reasonably necessary to protect that interest.
The case? Bartholomews Agri Food Ltd v Thornton  EWHC 648
Employers should review any restrictions in their employees' contracts of employment against dealing with former customers, using or disclosing confidential information or approaching former colleagues, to ensure the restrictions protect a legitimate interest and are no wider than reasonably necessary - or risk being unable to enforce them.