A modern, agile-inspired engineering framework for socio-cyber-physical systems — bridging disciplines and empowering engineers.
3SE is an engineering framework that unifies System Engineering, Safety Engineering, and Security Engineering under a single, coherent language and methodology.
Built on the values of the Agile Manifesto and designed for the complexity of modern socio-cyber-physical systems — including organizations themselves — 3SE provides the ontology, processes, and methodologies to engineer with clarity, consistency, and confidence.
Whether you are designing a critical infrastructure system, a connected product, or an organizational architecture, 3SE gives your teams a shared foundation to reason, communicate, and deliver together.
Engineering systems today means navigating a maze of siloed disciplines and fragmented standards.
The result? Projects that drift, risks that slip through the cracks, and engineers constrained by processes that were never designed for them.
3SE was born from a simple observation: the problems are systemic, and the solutions must be too.
Systems, safety, and security engineers work in parallel worlds — different teams, different vocabularies, different tools. Critical dependencies are missed. Integration happens too late, if at all.
ISO 15288, IEC 61508, IEC 62443, DO-178C… each standard speaks its own language. Without semantic alignment, compliance becomes a translation exercise rather than a quality driver.
Business management, project management, engineering management, and asset management each pull in different directions. Decisions are made in isolation, and trade-offs remain invisible until they become failures.
Traditional frameworks prescribe how to work rather than what to achieve. Engineers are micromanaged instead of trusted. 3SE returns responsibility and flexibility to the people closest to the problem.
At the heart of 3SE lies the 3SE Tetrahedron — a conceptual model that structures the engineering problem space into four interconnected domains:
| Domain | Description |
|---|---|
| Business | Business Management defines what is worth engineering from a commercial perspective, balancing investment against expected return across the full lifecycle. |
| Engineering | Engineering Management is the translation layer between commercial intent and physical reality. It owns technical feasibility and capability. |
| Asset | Asset Management takes care about physical and digital assets, their properties and lifecycle. It owns the organizational infrastructure that ensures consistent, repeatable, and compliant output. |
| Project | Project Management orchestrates the sequence of work, manages dependencies, and ensures that the deliverables reach the stakeholders within the agreed timeframe. |
These four domains are linked by six trade-offs — the axes of tension that every engineering team must navigate — all converging toward a single feasible design space: the solution that is technically sound, safe, secure, and viable.
The tetrahedron is not a process. It is a thinking tool — a map for reasoning about complexity before committing to solutions.
3SE is a complete engineering framework, not just a methodology. It provides:
A formal, shared vocabulary that aligns concepts across system, safety, and security engineering. One language for all disciplines. No more translation. No more ambiguity.
Clearly defined engineering and support processes, each with associated roles, workflows, and templates. Designed to be lean, adaptable, and built for agile contexts.
A structured language for expressing engineering artefacts consistently — from requirements to hazard analyses, from threat models to architecture decisions.
3SE's language is brought to life in JARVIS4SE, an open engineering tool that operationalises the framework. Explore it here: regis-casteran.gitbook.io/jarvis4se
A six-stage roadmap — from ad hoc to knowledge-based engineering — mapping the business gains at each level and the cost of staying behind. Built on the 3SE to help organizations assess where they are and plan where to go.
3SE is grounded in the values of the Agile Manifesto — adapted for the realities of safety- and security-critical system engineering. Rigour and agility are not opposites.
3SE positions against process replacing engineering judgement. This implies:
- Ownership of decisions
- Traceability of rationale
- Responsibility for consequences
- Professional competence
Checklist-driven compliance leads to:
- Cargo-cult safety cases
- Security theater
- Formal but hollow certification artifacts
3SE promotes evidence-based compliance which demands:
- Demonstrable hazard mitigation
- Threat validation
- Traceable requirement verification
- Test evidence
- Argumentation
Negotiation is episodic, alignement is continuous. This allows to:
- Reduce emergent systemic risk
- Minimize organizational drift
- Improve shared risk perception
Risk opacity implies:
- Siloed analysis
- Hidden assumptions
- Undocumented risk acceptance
- Fragmented assurance
3SE considers risk as being the integrating variable between system engineering, safety engineering, and security engineering.
Copyright (c) 2022 3SE — System, Safety & Security Engineering
