The Overton Framework formalized Protective Computing as a systems-engineering discipline for environments where the Stability Assumption—continuous connectivity, cognitive surplus, institutional reliability, non-adversarial access, and predictable infrastructure—does not hold. This Field Guide translates the theoretical framework into operational engineering posture. This document does not extend theory. It establishes the practical baseline for systems design under vulnerability states: illness, eviction, coercion, financial collapse, natural disaster, legal exposure, and institutional delay. The guide articulates five core protective principles:• Local Authority — authority must reside with the user, not remote gatekeepers• Reversibility — irreversible actions are catastrophic under stress• Exposure Minimization — surface area is liability in unstable conditions• Cognitive Load Awareness — design for users at their worst, not their best• Coercion Resistance — assume the device is not always private It includes a call for case studies, a roadmap for forthcoming operational artifacts (Protective Legitimacy Score rubric, Design Patterns v0.1, Implementation Companion, Threat Modeling Templates), and positions the discipline for empirical maturation. This is an operational companion to "The Overton Framework: Protective Computing in Conditions of Human Vulnerability" (DOI: 10.5281/zenodo.18688516).
K Overton (Thu,) studied this question.