A Masonic lodge often termed a private lodge or constituent lodge is the basic organizational unit of Freemasonry. It is also commonly, but erroneously, used as a term for a building in which such a unit meets. Every new lodge must be warranted or chartered by a Grand Lodge

but is subject to its direction only in enforcing the published constitution of the jurisdiction. By exception, the three surviving lodges that formed the world's first known grand lodge have the unique privilege to operate as time immemorial. 

A Freemason is generally entitled to visit any Lodge in any jurisdiction (i.e., under any Grand Lodge) in amity with his own. In some jurisdictions, this privilege is restricted to Master Masons (that is, Freemasons who have attained the Order's third degree). He is first usually required to check, and certify, the regularity of the relationship of the Lodge – and be able to satisfy that Lodge of his regularity of membership. Freemasons gather together as a Lodge to work the three basic Degrees of Entered Apprentice, Fellowcraft and Master Mason.