Is there much salary advancement as a psychiatric nurse practitioner?

I would assume so, but I'm not too sure

In general the answer is no. The limitation is your collections. If you look at salary surveys there is usually a $10k to $20k difference between a new grad and someone with experience. This is essentially the price the practice pays until the provider becomes efficient. Note, sometimes the employer forgets that you are more efficient and you have to change jobs to get more money. If you look on page three here:
http://www.aapa.org/images/stories/iu08incchange.pdf
It describes a pretty typical salary curve. The greatest changes are in year 1-4 and then they rapidy tail off and essentially disappear after year 12. This is probably due to the fact that after 10-12 years you are making what a practice can reasonably afford to pay you vs. collections.

The difference in law for example is that its a hierarchical system. Not everyone makes partner. Those that do make a lot of money. Those that don't put in a lot of billable hours so that the partners make a ton of money.

David Carpenter, PA-C

I feel as if law is a "go big or go home" type of profession, and it is very difficult to "go big." That being said, I would be willing to bet that you would make a lot of money as a psych np if you put in as many hours as a successful lawyer does.