This chapter, Budget Decision, addresses a range of economic and financial matters. Few studies or reports in the United States have focused on financial matters in the context of adapting to climate change, while many more studies have included climate adaptation financial matters in the international arena, especially and not surprisingly, in developing countries. As a result, this chapter seeks to identify some common features related to budgeting and finance decisions that could also inform U.S. and a broader set of financial decision-making. The chapter begins with a brief introduction to the U.S. federal government budgeting cycle that requires multi-year advanced planning. Structural constraints are discussed next as they pertain to the United States. Funding flow dynamics are introduced as factors in adaptation financial planning. Social influences discuss organizational and institutional factors having an effect on financial planning and decision-making. The chapter ends with a section on international efforts to institutionalize climate-related adaptive financing into routine planning and decision-making behaviors.