The alternative financing space has grown exponentially in the last few decades, namely as a consequence of the financial crisis, technological advancement, niche customer segments, and more recently the pandemic. Now, with the inclusion of Fintech, online lenders, crowdfunding, accelerators, venture capitalists, or angel investors, this funding channel is no longer seen as a substitute for formal financing, but rather a core one. This book is a comprehensive guide to alternative financing methods, offering insights into emerging trends, the role of FinTech, and the intersection of finance with sustainability, innovation, and entrepreneurship. It fills a knowledge gap by exploring innovative financing channels such as fintech, green finance, and venture capital as well as other non-traditional ways of raising funds, which have become crucial for startups and businesses. It discusses the impact of financial technology (FinTech) on these methods and their function in supporting entrepreneurship and sustainable business, while also examining the implications of these technological advancements in the wider financial sector. It addresses challenges and opportunities for entrepreneurs and explores how alternative financing options can support growth and innovation, particularly in the context of environmentally and socially focused ventures, including how to integrate economic, social, and environmental considerations. The emphasis on sustainability and green finance aligns with the growing global concern for responsible business practices and the Sustainable Development Goals. While the primary audience for the book is scholars, researchers, and students, the inclusion of case studies, and the exploration of various financing options, extends practical cues for policymakers and practitioners and contributes to the understanding of how finance, entrepreneurship, and sustainability intersect in real-world business scenarios.