I received a letter from my professional organization as it process my application to offer professional services to the public, ie essentially issue a business license for my corporation. The letter informed me that I should inform my current employer that I am offering professional services to the public, otherwise known as moonlighting. I can't moonlight of course until they issue the license.
While the letter would be appropriate accompaniment to the license they're jumping the gun telling me to so inform my employer before I can even legally offer services.
Similarly I had to get permission use my profession's name in my corporations business name because you can't use my profession's name in the name of a company unless you have the business license. Nowhere in the literature on the business license application process do you get this information. I knew to ask for a letter of permission because a colleague went through the process and informed me.
I once heard that laws are not there for the convenience of the people bound by them. The arcane and somewhat labyrinthian process of setting up a business offering professional services has put the lie to the aforementioned quote. It seems to me that laws are there expressly for the purpose of inconveniencing and confounding the people bound by them.