The TRE Open Suite is a new GA4GH Implementation Forum project that aims to develop a GA4GH-native framework and Software Development Kit (SDK) for deploying secure, interoperable infrastructure across hybrid multi-cloud environments. These may then form the technical foundation for Secure Processing (SPEs) and Trusted Research Environments (TREs). The project introduces a modular architecture supporting pluggable trust-enhancing technologies — such as Crypt4GH, Homomorphic Encryption, Attested TLS, and Differential Privacy — while aligning with policy frameworks like EOSC-Entrust and the Five Safes. By combining GA4GH standards with formalised digital trust models, the TRE Open Suite supports scalable, secure, and privacy-preserving research collaboration. This initiative not only enhances interoperability and user control in federated environments, but also contributes to the evolution of GA4GH products and practices to meet emerging security and governance challenges.