This book presents the theoretical debate on economic development and stagnation in a clear and organized manner. It examines the complexity of economic theory, shaped by the interactions of diverse agents—firms, households, governments, and banks—across various markets. Despite its abstract nature, economic theories can be made accessible through careful explanation. Here, André Nassif covers the main theoretical foundations of economic development, incorporating key contributions from Latin America, offering a comprehensive overview that critically engages with these theories while maintaining academic rigor.