Though bars like this have been steadily declining in number since the end of Japan's bubble era, you may still run across a few while walking through the city (especially Ginza). As the name indicates, members-only bars require you to be a member yourself or be the guest of a member. Usually you'll be required to pay some kind of registration fee in addition to yearly membership dues for the privilege of drinking at that particular bar.
I’m Whiskey Richard, and I am the founder of nomunication.jp. I’ve lived in Tokyo for over a decade, and I am a certified Shochu Kikisake-shi/Shochu Sommelier (焼酎唎酒師), Cocktail Professor (カクテル検定１級), and I hold Whisky Kentei Level 3 (ウイスキー検定３級). Click here for more details about me and this site. Kampai!