There is a lot of advice out there on how to go about building your own custom exception classes. A lot of these sources are at least partially correct. Some are totally wrong. Some even advocate abandoning the base System.Exception class altogether, but that’s throwing the baby out with the bathwater, in my opinion. None that I've seen show how to serialize/deserialize your custom exception class should it have additional data in it's subclass. It’s enough to make one despair of ever finding the “right” way to build an exception class.