"Everybody wins,"
or it should be, if I had a motto. At least this is what I consistently shoot for. Whatever it is, the attempt should be made to as far as possible make sure everybody involved wins at least something. It's not actually possible of course, and almost always even the people winning don't get exactly what they wanted, Still, it's a sursprisingly powerful formula for getting stuff done. Requires working out what the people you're dealing with not just think they are interested in, but more importantly what you might interest them for.
"Always hire people smarter than yourself",
so far has also proven a great success. Not only do they make you look good, if you know how to handle them, but should things get sticky, it's not as if you're chucking people without resources and options out into the street. (The downside is that you might lose them simply because they found an even more interesting opportunity. Still, smart people tend to know smart people, and recommend you as an employer even when they leave.)