This document discusses the nature of entrepreneurship and entrepreneurial thinking. It defines entrepreneurship as acting on opportunities to introduce new goods, services, or organizing methods. Entrepreneurs think structurally, using bricolage to apply resources to problems. They use effectuation to select outcomes based on what they have rather than focusing on a desired outcome. Entrepreneurial mindset and cognitive adaptability allow entrepreneurs to rapidly sense and act under uncertainty. Intention, self-efficacy, and desirability of outcomes influence entrepreneurial action. Education, age, and work history impact entrepreneurs, as do role models and support systems. Sustainable entrepreneurship focuses on preserving sustainability while pursuing opportunities.