ESP refers to an Email Service Provider. These are companies/applications that specialize in email marketing or bulk email services. Because they are specialized applications, they offer rich functionality for sending and tracking email. Our flagship product, LeadConduit, is designed to integrate directly with an ESP. A common way that ESPs are used in conjunction with LeadConduit is to send real-time auto-responder emails to incoming leads. Clients may even want to send a series of triggered emails to new prospects. We allow clients to use any ESP that they want for sending emails. In addition, we also provide an email marketing solution that is integrated with LeadConduit.