You may have some, or many, clients who you've turned into advocates for you and your business by delivering superior service and maintaining a meaningful relationship with them. Beyond your clients, there are many opportunities for relationships with people who can provide you with a steady stream of referrals - people who may never become clients. These people are often referred to as Centers of Influence. I call them Referral Alliances.
Every industry has some traditional referral alliances.
In the financial services industry they are accountants and attorneys. In the printing industry it's other salespeople who offer non-competitive services. For mortgage brokers it's real-estate agents. You get the idea. If you haven't already, you should develop significant relationships with a few of the traditional referral alliances in your industry.