I suggest reading this Cook's Illustrated - The Basics of Brining (PDF) article.
I use their basic brine all the time.
This article taught me two cool things I didn't know about brining.
Adjust the amount of sugar & salt downward for high heat applications.
Decreasing the amount of sugar ensures that the exterior of the meat doesn't burn.
Prior to learning this I had a few "issues" with this mishap Air drying chicken and turkey in the fridge after brining allows the skin to dry out, enabling it to crisp nicely when cooked.
If you aren't familiar with Cook's Illustrated, they bill themselves as America's Test Kitchen.
They will take a recipe and beat on it with dozens or more variations tweaking and analyzing it as they go, until they come up with the "ideal" something or other.
In this case, it's brining.
With this as a base you have a lot of opportunity for experimentation.
I usually add very hearty aromatic spices to mine.
Some possible additions and substitutions: Whole peppercorns Ancho chiles Whole Allspice Cinnamon Cloves Candied Ginger Brown sugar in place of sugar Substituting some vegetable stock for water
**Use the lowest sodium stock possible, and adjust salt accordingly.
I don't have a hard-and-fast rule here, but I tend to go with about 20% less salt than the "basic", more or less.
Another thing addressed by this article is what meats should and shouldn't be brined.
The short version is lean mild meats are suitable for brining, fatty meats or those often cooked rare/med-rare do not benefit.
Suitable Cornish Hen Chicken Turkey Pork
Some seafood Whole side of salmon (grill roasted or smoked) Shrimp
Unsuitable Beef Lamb Goose Duck
cooking.stackexchange.com/users/60/hobodave
Modern meat not being as fatty as the meat of yore, will appear dry when cooked.
Brining helps the meat remain juicier.
To brine chicken, immerse it in a 10% salt solution (by weight) and keep it in the refrigerator from 3 to 24 hours.
To make a 10% solution, use 1 cup of kosher salt for every 1.4 quarts of water (5.6 cups).
Cooks Illustrated , a cooking magazine that develops and tests recipes, has a good brining guide.
One may think that making the brine stronger would make the chicken juicier.
That is not the case.
Above concentrations of 13%, the brine dries the meat .
I have tried adding spices to the brine, but I have never been able to detect their flavors in the meat.
Sometimes I replace some of the salt for sugar, as suggested by @Adam
Shiemke.
See the Cooks Illustrated guide for measurements with sugar and other types of salt.
cooking.stackexchange.com/users/183/papin
I'm going to differ with papin on a few points; I would suggest a 5% by weight solution, rather than 10%.
Partly this is economy -- 10% by weight with a gallon of water is .8
lbs, or nearly a whole box of kosher salt!
But also, I learned to do a 5% brine from Ruhlman in his Charcuterie book, and this is also what Thomas Keller suggests in his cookbooks.
So 5% is good enough for me.
Regarding flavoring the brine, the primary impact the brine will have is saltiness, however, if you aggressively flavor the brine, you can get other flavors into the chicken and it can be absolutely delicious.
From memory, the brine for fried Chicken in Keller's Ad-Hoc cookbook involves a gallon or so of water, (maybe 1.5?), 5% salt solution, 24 <- bay leaves, four or five lemons, a bunch of garlic and quite a lot of thyme, like 6 oz or so.
I don't recall if there was sugar in this brine.
This is all boiled to get the ingredients mixed, then chilled.
The chicken then went in for 12 hours.
This brine was a pain to make.
It was also nicer than some soups I've made -- it looked gorgeous, smelled amazing, and I froze what I didn't need for the chicken.
I would probably be happy to have a picture of it on my kitchen wall.
The flavors definitely made it into the meat, including the herbs, but hopefully this helps illustrate how assertive the seasoning needs to be to get any flavor in there.
cooking.stackexchange.com/users/982/Peter V
Kosher meat is essentially pre-brined.
Part of the preparation of meat for kosher kitchens is to pack it in salt (where kosher salt got its name) to draw out the blood.
Many recipes that call for brining the meat first will say to skip that step if you're using kosher meat.
Of course, if you want to add flavorings other than salt, kosher meat isn't your best bet.
cooking.stackexchange.com/users/1887/Martha F.
The reason brining helps to make meat and poultry taste different is because it adds moisture to the flesh through a process of osmosis.
The basic ingredients are simply salt and water, however, you can also add your own particular flavours to the brine, such a spice mix.
whatever flavours you add, will be taken-up by the meat or poultry.
The amount of salt and water used will depend, but a good starting place is one cup of salt to a gallon of water.
the amount of time required for brining will depend on what you have to brine.
A whole chicken, for example, may take 24 to 36 hours, followed by several hours in the fridge for the flavours to 'set'
cooking.stackexchange.com/users/115/Pulse
What are the basics and options of brining meat, for example chicken?  I ate at a restaurant in Santa Fe that specialized in brining and the chicken was amazing.  Id like to know what the process is and how much variation there is.
What are the basics and options of brining meat, for example chicken?
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<chicken><brining>
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Brining uses osmosis to add moisture to the flesh and make it juicier. Cook's Illustrated has a useful article on this topic called The Basics of Brining. Brining is a process of soaking meat to add moisture and stop it from drying out during cooking.
Try reading Cook's Illustrated on the basics of brining. Brining adds moisture to the meat which makes it juicier.