I try to avoid re-blogging, (lots of blog entries already exists about the Enterprise Library (Entlib)).  Entlib was published to MSDN 1/28/2005, and I must say it is worth downloading and reviewing.  However I have been reviewing Entlib and I am impressed with the amount code (number of components), I can just configure and use.  I can now give my customers on guidance implementing business rules and shared data types common to their organization.

Download Enterprise Library here

.  Happy coding.