This Special Issue brings together the latest research on fermentation processes, with a focus on yeast, biofuels, and value-added products. As the demand for sustainable energy sources continues to rise, biofuel production and the generation of value-added byproducts provide an exciting opportunity for enhancing the efficiency and profitability of production systems. This collection highlights the latest research developments into these fields, offering valuable insights for researchers, industry professionals, and producers seeking to innovate and optimize their operations.