The number and diversity of energy finance programs have increased dramatically in recent years. Likewise, there is a growing interest among different types of financial institutions in participating in local initiatives. However, finding a financial partner that best fits a particular program can be a challenge. This paper attempts to catalogue the different categories of institutions in the marketplace so that readers will be more equipped to determine which type may offer the best fit for a local initiative. In addition, the paper offers descriptions of the different types of loan structures and mechanisms most often used in energy finance.