This report by the NGMN Alliance provides recommendations for securing 5G networks through the use of network slicing. The report is version 1.0 and was published on April 27, 2016. It is considered a final deliverable and is publicly available. The report was written by Rémy HAREL and Steve BABBAGE, with contributions from the NGMN 5G security group. It was approved by the NGMN Board on April 29, 2016. The report is confidential and may not be used, disclosed or reproduced without the prior written authorization of NGMN Ltd.