As far as I know, the use of the word "herd" in this context was first used by Dan Kennedy. I have learned much from Dan, including my appreciation for the importance of not just marketing to people who need my services - new clients - but also of building and taking care of the herd. (www.dankennedy.com)
What would your answer be if someone asked you to name the most important asset of your practice? You may own your own building, your technology may be top of the line, and your partners and staff may be committed to the practice.
However, if you do not understand that the most important asset of your practice is your "list", then you are on the road to working too hard and spending too much money building your practice.
The "List" is essential to building and maintaining an active, enjoyable - and, yes, lucrative - practice. Every client you represent, and even those you end up not representing, has tremendous long-term value to your practice. Not surprisingly, most lawyers do not understand this and do nothing to preserve this value.
The "List" includes your current and past clients, friends, family, vendors, personal contacts. These people will help build your practice and make your marketing dollars stretch for three very important reasons:
They already KNOW OF you.
They probably TRUST you and your knowledge about personal injury law.
They probably also LIKE you personally.
These are the people who are most likely to think of you and recommend you when they have a problem, or know someone who has a problem that you can help with. These are the people who are most likely to tell others, free of charge, about you. They can become your own "herd" of fervent followers, eager to tell others about you.