Navigating Sustainability: The Role of Consumer Psychology in Shaping Sustainable Behavior

The gap between what consumers say and do threatens the effectiveness of sustainability initiatives. An explanatory-sequential mixed-methods design modeled survey data from 410 Generation Y consumers. We unpacked the statistics through 12 in-depth interviews to probe the psychological levers that could close this gap. A conceptual framework—melding the Value–Belief–Norm theory, the Norm Activation Model, and the Theory of Planned Behavior—posited that Environmental Concern (EC) and the socio-moral emotions of Consumer Guilt (CG) and Ascription of Responsibility (AR) shape Sustainable-Consumption Behavior (SCB) via Perceived Consumer Effectiveness (PCE), with Awareness of Consequences (AC) as a theorized catalyst. PLS-SEM confirmed the framework: EC was associated with SCB (β = .75); CG (β = .32); and AR (β = .42) boosted PCE; PCE, in turn, mediated the EC → SCB pathway (indirect β = .15). AC moderated the EC → PCE link (β = .22), indicating that concrete knowledge intensifies the sense of personal impact. Thematic analysis corroborated and enriched these findings, surfacing five themes—Concern–Action Gap, Empowered by Impact, Guilt as Moral Driver, Owning the Problem, and Awareness as Catalyst—that mapped neatly onto the SEM paths. Drawn from educated, urban Turkish Gen-Y consumers, this convenience sample allows analytical transfer to similar emerging-economy groups but not statistical generalization. The innovation of this study lies in its integration of three psychological theories into a unified model that is theoretically grounded and practically predictive, bridging emotional, cognitive, and behavioral drivers of sustainable consumption. Pairing vivid consequences with personal-impact feedback most effectively turns EC into lasting pro-environmental behavior.