Fighting an employer or becoming a whistleblower can lead to retaliation and undermining tactics. "Georgina Halford-Hall, chief executive of WhistleblowersUK, says the stress of fighting a bad employer is all-consuming. But, however difficult, it is important to continue doing the everyday things you enjoy. Drawing on personal experience, she recommends finding an independent mental health professional to offload on." Writing in the Financial Times, Alicia Clegg investigates.