This document discusses the stages of maturity that startup ecosystems pass through, from nascent to evolving to mature to self-sustainable. It defines each stage, from a nascent ecosystem just starting to form, to an evolving ecosystem with some successful companies, to a mature ecosystem with hundreds of startups and investment deals, to a self-sustainable ecosystem with a strong network of entrepreneurs supporting long-term growth. It also discusses factors that contribute to an ecosystem reaching maturity, like the presence of successful entrepreneurs who mentor newcomers and support the ecosystem over the long run.