In the past few years, Spain's freewheeling Mediterranean port city of Barcelona has come to rival Amsterdam as Europe's premier cannabis scene, with a proliferation of clubs where merry-makers openly light up. Now the Public Health Agency of the Generalitat de Catalunya has proposed tight new measures to regulate the clubs, and discourage the burgeoning cannabis economy. The Generalitat, the regional government of Catalonia, has broad powers under Spain's decentralized system, although it cannot override Spanish national law. And Spanish law allows private cannabis use—or for users to unite in non-profit associations to smoke together. As Amsterdam has imposed restrictions on cannabis cafés, the number of clubs in Spain has surged from some 40 in 2010 to more than 700 today—more than half in Barcelona, the Catalan capital. But emergence of Spain as the "Holland of the South" has been viewed with dismay by Catalonia's straight-laced business elite.