Yes. You can hire a person or company to do it. It helps a lot and can be worth it if you have enough business. Leverage is definitely a good thing. Having someone else handle the calls and followup leaves time to focus on core business responsibilities.
My assistants pre-screen callers, handle scheduling, make outbound followup calls, and followup on action items. They also handle marketing and other aspects of my business if I don't have time that week to do it myself. It can get pretty expensive.