Every successful negotiation requires that from the outset you know yourself and as much as possible, know your negotiation partner.

You can never be too prepared for a negotiation — and you can all too easily be unprepared.You should also try to learn as much as you can about the specific circumstances surrounding the negotiation.

If you’re looking for a doctor, lawyer, accountant, real estate agent, or another professional you intend to put your trust in, always interview them before signing on. In addition, insist on references and be wary if someone refuses; it may signal that they don’t have satisfied clients. Lawyers, doctors, and financial advisors are licensed by legal, medical, and financial organizations; check those organizations for disciplinary actions.

Also check the Better Business Bureau for complaints.Find out how independent rating agencies (Consumer Reports, Angie’s List, and so on) rate a product, service, or company. The Internet makes these inquiries easy. You don’t even need to own a computer; just go to the public library.

Never allow yourself to be pressured into a decision. Always get the facts, consider them carefully and then make a decision when you are ready. When you begin any negotiation, find out who has authority to close the deal. This can be a relatively simple task, or it may be a constantly moving target. Whoever has that authority at the beginning of a negotiation might not maintain it; your job is to continually probe, and adjust as necessary.

You might also ask your negotiation partner to tell you a bit about the decision-maker(s), their past decisions, how they might view the deal you’re working on, or what might make them disapprove its terms. If the approval process will be cumbersome, plan for the additional time required to have the negotiation approved. This will help you avoid being frustrated by the inevitable delays.

Excerpt from The Transformative Negotiator: Changing How We Come to Agreement from the Inside Out. By Michèle Huff, J.D. UNHOOKED BOOKS.