User-friendly interface: The ESP should have an intuitive and easy-to-navigate interface. Segmentation: Ability to segment your email list based on various criteria to target specific groups effectively. A/B testing: Tools to test different email versions to determine which performs better. Templates: A range of customizable email templates to suit your brand's needs. Analytics: Detailed reporting and analytics to measure the success of your campaigns. Customer support: Reliable and accessible customer service to resolve any issues promptly.