A real estate investment association or REIA may be a for profit or not for profit organization. The typical mission of a REIA is to provide a forum both for networking as well as for professional level training in real estate investment. The goals, methods, and tools available to a professional real estate investor are generally not the same as a typical real estate transaction. For example: a professional investor may do hundreds of deals without even once obtaining a commercial loan to do so. REIAs are a place for aspiring real estate investors to learn about transaction engineering, or ways to put together deals involving multiple parties in such a way that each party benefits from the transaction.
Local REIAs can be found all over. Sometimes they can be in the form of an informal mastermind group of perhaps 6-20 individuals. Other times they may be large groups encompassing hundreds or even thousands of members.
In the US there is a National REIA which oversees multiple chapters in each state.