Irregular and unaccountable transactions, cyber threats, non-user-friendly inefficient or impractical banking processes, complex contracting procedures and cumbersome financial market and insurance infrastructures constitute obstacles to European open market development. CRITICAL-CHAINS delivers a novel triangular accountability model and integrated framework supporting accountable, effective, accessible, fast, secure and privacy-preserving financial contracts and transactions to protect against illicit tranasctions, illegal money trafficking and fraud on FinTech e-operations. This is an innovative cloud-based “X-as-a Service” solution stack including several layers: 1) Data integrity checking by involving financial institutions in the distributed Blockchain network; 2) Transaction and financial data flows analytrics, modelling and mining; 3) Threat Intelligence & Predictive Modelling for Inter-Banks and Internet Banking, insurnace and financial market infrastructures; 4) Multilateral Biometric-based and Role-based Authorisation & Authentication; 5) Hardware Security Module (HSM) enabled Cyber-Physical Security, embedded systems & IoT security for secure access using Security-Privacy-Contexts Semantic Modelling; 6) Secure and smart use of Blockchain based on keyless signature infrastructure and hybrid (a)symmetric cryptography utilising truly random key generation. CRITICAL-CHAINS is to be validated within 4 case studies aligned with 3 critical sectors: banking, financial market infrastructures and the insurance sector. This will evaluate system reliability, usability, user-acceptance, social, privacy, ethical, environmental and legal compliance by scrutiny of the geo-political and legal framework bridging the European economy with the rest of the world. The Consortium respresents a strong chemistry of relevant expertise and an inclusive set of stakeholders comprising end-users (customers), CERTS, the financial sector (Banks & CCPs) and the Insurance sector