This document is the first section of a handbook on building mobile money agent networks. It discusses different approaches to defining agent roles, with some networks assigning uniform roles to all agents while others differentiate roles. The most common roles involve registering customers, educating them, and facilitating cash-in/cash-out transactions, though these roles can be separated or combined in various ways. The handbook uses M-PESA in Kenya as an example of a uniform agent model and compares this to models used by other mobile money providers that differentiate agent roles.