The rapid evolution of blockchain technology within healthcare presents unparalleled opportunities for advancements, including enhanced patient data security, decentralized systems for trustless operations, and transparent supply chain management. However, as blockchain reshapes the healthcare landscape, it demands a robust ethical framework that guides its design and implementation. "Ethics of Blockchain by Design" emphasizes embedding ethical principles at the heart of blockchain innovation, fostering public trust, equity, and long-term societal benefits. This paper also proposes a set of best practices guidelines on ethics of blockchain by design.

Blockchain applications in healthcare have grown rapidly and it includes record keeping, clinical trials, medical supply chains, patient monitoring, etc. where Blockchain characteristics are needed to improve safety, privacy, and security. Blockchain Technology is one of the biggest disruptive technologies today. However, Porru, et. al (2017) have reported it lacks processes, tools, and techniques. Therefore, this paper provides a systematic framework for a secure and sustainable software engineering framework for healthcare blockchain applications. Secure and Sustainable Software Engineering Framework for Healthcare Blockchain Applications (S3EF-HBCA) significant contribution includes requirements engineering for healthcare, business process modelling for healthcare, domain modelling for healthcare, a reference architecture for healthcare, and validation by case study on Electronic Healthcare Record Management System (EHR), and simulation with Business Process Modelling Notation (BPMN) tools. The simulation shows it has taken 10.45 minutes to process 100 instances of real-time data and service requests. The overall result shows encouragement in terms of process, tools, standards, and testing.