This document discusses eAlert, a leading emergency alert notification system used by government agencies and organizations to deliver time-sensitive messages. eAlert required a delivery system that could handle high volumes, satisfy each client's unique sending requirements, and provide reporting. Port25's PowerMTA software was selected as it could flexibly integrate into eAlert's system, configure a VirtualMTA for each client, and deliver over 5 million messages per hour with robust reporting and authentication tools. PowerMTA's performance and features enabled eAlert to effectively deliver billions of alerts annually.