Is the reputed "hardest test of knowledge" in the wine world worth taking? This week, 75 highly motivated oenophiles are pursuing wine geekdom's ultimate gong: the right to be called a Master of Wine, or MW. It's not a drinking contest: It is a four-day test of wine knowledge administered by the London-based Institute of Masters of Wine, or IWM. The annual exam is given simultaneously in three locations—London, Sydney, and Napa—and is notoriously difficult: In the past decade, an average of just eight people have passed per year, and there are fewer than 300 MWs in total. It is surely the world's most exclusive wine club. But while earning the MW is a boffo achievement, does it have any practical value, and does oenophilia really need forms of accreditation? Isn't the right to procure alcohol enough?