According to the current law, you cannot “buy” weed in Barcelona. On the other hand, you can “acquire” it, primarily by “contributing” as a member of the cannabis club(s) you join. So, don’t expect to “buy” your weed at a cannabis club – and it’s recommended not even to use the “b” word. You can still “get” it or “acquire” it at the club, but it’s just a matter of semantics.
Also, do not purchase weed on the street. That is definitely considered illegal and can quickly put you in legal jeopardy, just like being caught publicly transporting cannabis. Therefore, when you do legally “acquire” your weed, be sure to hide it well when you’re transporting it home.
With that in mind, the best bet for cannabis connoisseurs is to become a member of a cannabis club in Barcelona, which currently has over 200 cannabis clubs that are considered private cannabis associations. Keep in mind that they are not public stores or coffee-shops, and you must complete a full membership registration and pay the application fee in order to enter.