Barely a day goes by without a website, campaign or competition cropping up, promising to harness the collective wisdom of crowds for the benefit of brands. Consumer generated inputs are playing a more and more prominent role into research, innovation and planning. However, it is still not very clear what are the most suitable approaches, frameworks and methodologies available for for doing this. This presentation, recently discussed at a number of conferences in the UK, Spain and Italy, looks in particular at crowd-sourcing and co-creation: when to use them, what are the advantages, the drawbacks and the workarounds, what are the deliverables and how could these grassroots practices fit into the existing marketing processes. Using crowd-sourcing and co-creation as complementary frameworks is key to harness the wisdom of the crowds both at an individual and group-thinking level, bringing together bottom up and top down approaches, online and offline, to make sure the richness provided by mass collaboration is effectively shaped and leveraged by informed strategic thinking and expert insight.