I come from the school of thought that all parties need to walk away from the table feeling like a winner. 

I agree with Nina Hollander  Desmond. 

Lots of good advice in comments before mine so I will just drink my coffee & go to Easter service.

Listen and digest before you respond!

This is an excellent question.  However, your question has been publicly posted and I don't disclose negotiation tactics publicly as it could compromise negotiations for my clients by letting the other side know what tactics I use.

It depends on the situation and the parties with whom I'm negotiating. 

In ALL negotiations, just like a debate, YOU need to know your subject backwards and forward.   YOU need to know YOUR adversary's strong points and vulnerabilities.

In the negotiations, YOU want to be firm but flexible and know in advance when and where to do each.   Finally, each side needs to feel they got something even if they gave ground on other points.

As many have said here, a good negotiation is when it ends up being a win - win for ALL parties ! 

I "make them an offer they can't refuse."  And then there are horses heads... no wait, too much Godfather.

In all seriousness, one of the best lines I've ever heard was from a plumbing company we were negotiating with.  The agreed upon price was higher than we would have liked and lower than he would have liked.  He said "You know how I knew it was a good deal to make?  When both parties feel uncomfortable.  Both can feel like winners then."

Nina Hollander has this one.  

if you stop to consider that everyone wants the same thing, once you get yours, help them, get theirs....works better than not doing it...to be sure

Desmond Neoh Win-Win!

After 30 years in real estate i have fine tuned teh art of marketing to attract offers. Getting offers is the biggest part as without them you can not negotiate. Once having them asking each buyer for their highest and best is a good start. From there you can work with the best to make it better for your client

There are many good ways to negotiate.

Gather as much information about the people you are negotiating with so you can speak their language.

Depends on each situation and each parties ability to walk. One way is the BATNA process (Google it).

Desmond Neoh there  are different styles of negotions - and to be an expert at that, I think you'll have to get the experience of learn... 

Wish I could give all advice here in this small area...

That's a complext question. My feeling is it needs to be a win/win, and depending on the circumstances there are different ways to accomplish this

Win Win.

Whether or not people are aware of it, they spend a significant time of their day using their negotiation skills either in formal or informal routine interactions. It is a skill, some are good in it, some are not. Just work on it. Practice makes difference:) 

I am straight forward and honest...Don't need anymore tactics.

every situation is different and requires a different tactic.... 

I agree with Wayne Martin that listening is your first step. Know what really matters and what you are willing to change.

Absolutely try to strive for a win-win negotiation, where everyone feels good about the transaction. Makes for much easier negotiations down the road and a smoother closing.

parked and reading

Present and accept the best offers.

It is not one-size-fits-all.  Tactics vary by the situation.  We want to cause the other side to feel like they won ... even if they didn't. 

Honesty

Know what you client is willing and able to do.

Then exceed their expectations.

To do that you need to know exactly what information the other side has, if any, and be prepared.

Commit to your client, don't get connected to the outcome.

Know your walk away number and conditions prior to entering into the negotiations.