The role of the internet is increasingly pertinent in the daily lives of both clinicians and patients. We present two case reports, concerning patients recently presented to our service, involving beliefs concerning the social media website, Facebook. We consider the basis of a delusional experience from both categorical and dimensional perspectives. We consider the context of the nature of social networking media and the internet, including examples of how it has been used therapeutically, as well as the potential for detrimental use. Whilst keeping the principle of a delusion in mind we also explore some of the challenges that are presented in the assessment of such beliefs and how, or indeed whether, to incorporate them into the understanding of a patient's presentation. We also briefly consider the impact that beliefs arising from and incorporating social media and the internet may have on the practice of clinicians, descriptive phenomenology research, diagnosis and management of mental disorder.
