This is the first book that uses the Harris – Todaro (H-T) model to study contemporary economic issues in developing countries, with a particular focus on China. The zenith of research utilizing this model occurred in the 1990s, primarily addressing the impact of economic policies during labor migration on wages and employment across various sectors, international trade, urban unemployment rates, and social welfare. After nearly four decades, research in this area gradually faded from the spotlight. Post-2010, however, there has been a resurgence in H-T model studies. Scholars have begun using this model to explore contemporary issues, revealing unprecedented insights and showcasing its robust applicability and vitality. The book features 13 papers authored by contributors since 2018, each utilizing the H-T model and published in various academic journals. It delves into pivotal issues of contemporary economic development in developing countries like China, including dual agricultural economy, producer services, foreign direct investment, agricultural pollution, migrant workers’ remittances, and agricultural human capital investment. The book constructs general equilibrium models by integrating these topics with the H-T model, providing a framework to assess the impact of economic policies. Methodologically, it goes beyond conventional approaches by introducing constant elasticity of substitution functions and other methods to precisely express contemporary economic problems. Numerical simulations to examine the impact of economic policies are also used. Beyond presenting solutions to the current economic problems in developing countries, this book provides academic references for economic theory researchers.