These guidelines for the management of congenital ichthyoses have been developed by a multidisciplinary group of European experts following a systematic review of the current literature, an expert conference held in Toulouse in 2016, and a consensus on the discussions. They summarize evidence and expert-based recommendations and intend to help clinicians with the management of these rare and often complex diseases. These guidelines comprise two sections. This is Part one, covering topical therapies, systemic therapies, psychosocial management, communicating the diagnosis and genetic counselling. This article is protected by copyright. All rights reserved.