As digital transformation accelerates, organizations must manage cloud costs while addressing environmental sustainability. This chapter introduces Sustainable Financial Operations (FinOps)—an evolving practice that integrates financial accountability with carbon-conscious cloud operations. Once focused solely on cost optimization, FinOps now expands to include emissions reduction, driven by regulatory mandates and stakeholder expectations. The chapter outlines tools and strategies—such as rightsizing, carbon-aware scheduling, and geographic optimization—that help organizations measure and minimize their carbon footprint associated with cloud usage. It also explores the management of Scope 1, 2, and 3 emissions, the importance of transparent reporting, and collaboration with cloud providers. A maturity model is proposed to guide the journey from basic visibility to predictive, sustainable optimization. Key enablers include cross-functional teamwork, upskilling, and cultural change, as well as addressing challenges such as data inconsistency and cost-carbon tradeoffs. Sustainable FinOps is presented not just as a technical fix but as a strategic shift that enables resilient, efficient, and environmentally responsible cloud infrastructures.