Social Ecological Model: S-Tier Behavioral Designer’s Guide
Short answer: The Social Ecological Model places any behavior inside five nested rings of influence: Individual, Interpersonal, Community,…
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The Blog
Ideas on motivation, behavior & design.
Deep dives on the psychology behind why people do what they do — from Yu-kai Chou, creator of the Octalysis Framework. Pick the topic that matters to you.
Nationcraft Analysis: Venezuela Reform Playbooks 2026
Eight Reformer Playbooks Venezuela’s Variables Reject — And the Three That Actually Fit Every time a Venezuelan transition…
Theory of Planned Behavior: S-Tier Behavioral Designer’s Guide
Short answer: The Theory of Planned Behavior (Icek Ajzen, 1991) says actions follow intentions, and intentions come from…
Health Belief Model: S-Tier Behavioral Designer’s Guide
Short answer: The Health Belief Model explains health behavior through Perceived Susceptibility, Perceived Severity, Perceived Benefits, and Perceived…
Sludge (Sunstein): S-Tier Behavioral Designer’s Guide
Sunstein's Sludge: excessive friction that blocks beneficial action. The three-cost taxonomy and the audit every Octalysis review should…
Post-Traumatic Growth: S-Tier Behavioral Designer’s Guide
Tedeschi & Calhoun's Post-Traumatic Growth — the five domains where schema rebuilding after trauma produces lasting change, plus…
Ego Depletion: S-Tier Behavioral Designer’s Guide
Baumeister's willpower-as-muscle theory failed two pre-registered replications. What survived, what replaced it, and how to design around the…