The article considers the concept of startups and ecosystems of startup development. It investigates the innovativeness ratings of countries and regional ecosystems of startups and the factors influencing the successful development of startups. The article considers the ranking of the best regional startup ecosystems in the world. It covers the experience of the leading regions, whose effectiveness is driven by attention to financing, networking, expanding access to markets, attracting and nurturing talents, accumulating experience and scientific development. Particular attention is given to the impact of the specialization and effectiveness of the regional focus strategy. Based on the methodology and results of the Global Startup Ecosystem Ranking 2019, authors have empirically investigated the startup ecosystem of the Lviv city. Authors described and systemized the startups operating in the city, the elements, and dynamics of the urban startup infrastructure. The preconditions for successful development of startups - financing, talents, experience, connectedness, access to markets - have been identified. The effectiveness of the activity of city authorities, the local policy of promoting the startup environment development - documents, measures and results – have been investigated. The main factors of Lviv’s regional leadership in the development of digital startups in Ukraine are: the dynamic development of the IT industry, the development of digital competencies and the concentration of talent in leading universities, the development of corporate universities and innovative infrastructure, the development of infrastructure and comfort in the city. For the development of the Lviv startup ecosystem, it is recommended to focus the efforts on further accumulation and transfer of experience, retention of talents, improvement of technology transfer systems, focusing on areas of exclusive competence while expanding access to finance and the global market.