This study examines the interplay between entrepreneurial cognition, institutional voids, and venture evolution in Nigeria’s opportunity-constrained economy. Nigeria, characterized by high unemployment, limited formal support structures, and structural inefficiencies, presents a unique context for understanding how ventures emerge, adapt, and survive despite systemic constraints. The study conceptualizes entrepreneurial cognition as the mental frameworks, heuristics, and adaptive reasoning processes that guide opportunity recognition and strategic decision-making. Institutional voids manifested in limited access to finance, regulatory inconsistencies, and weak infrastructure create both challenges and opportunities for entrepreneurs, shaping the strategies and trajectories of ventures. Through a comprehensive review of literature and conceptual analysis, the study highlights how cognitive processes mediate the effects of institutional voids on venture evolution. Entrepreneurs navigate constraints through effectual reasoning, resource bricolage, informal networking, and iterative learning, enabling ventures to survive and adapt in highly uncertain environments. The analysis identifies key patterns of venture initiation, growth strategies, and survival mechanisms, emphasizing the centrality of cognitive agility and contextual awareness. The findings contribute to theory by integrating entrepreneurial cognition and institutional perspectives, demonstrating that venture evolution is a product of both internal cognitive capacities and external structural conditions. Practically, the study offers insights for entrepreneurs, policymakers, and support organizations, highlighting strategies to enhance resilience, adaptability, and sustainable growth. The study concludes that effective entrepreneurship in opportunity-constrained contexts requires a combination of cognitive skill development, adaptive strategic practices, and targeted interventions to mitigate institutional gaps, offering a framework for understanding and promoting venture success in Nigeria and similar emerging economies. 

Keywords: Entrepreneurial Cognition, Institutional Voids, Venture Evolution, Opportunity, Constrained, Economy.