Book excerpt: Since its first use in 2008, blockchain technology has come a long way. It has developed to distributed virtual machines that execute smart contracts and much more. Blockchains have a potential application in many industries and offer great innovation potential for organizations. With all the opportunities and value new technologies can deliver, the risks are often neglected. This is why in this book, Florian Mair identifies risks to data integrity on blockchains. Further he assesses the differences regarding data integrity among private and public blockchains. Mair has found overall 11 risks which are applicable to public blockchains. But even though some of them got rated as a high risk there is currently no evidence that a blockchain should be considered insecure. The author discusses some actions that can be taken to mitigate the identified risks. In this book: - data security; - risk management; - bitcoin; - risk assessment; - Distributed Ledger Technology