This is an interesting article discussing how fairtrade works on the ground in Nigeria, Ghana, Cameroon and Côte d’Ivoire. Here's an excerpt:

In Côte d’Ivoire and Ghana, Fairtrade has become linked with the “cocoa mafia” and the historically corrupt state Cocoa Board, respectively. When FAIR team member Selay Kouassi first attemped to report that story, he was threatened and eventually forced to go into hiding. All this suggests that Fairtrade is not just ineffective; rather, it has been subjected to and complicated by the realities of the post-colonial African economy, namely elite dominance and the inability of the state to fully establish a legitimate monopoly on violence.

But the report’s most damning finding is that, of everyone involved with the Fairtrade program, Fairtrade itself walks away with most of the money. In the Netherlands, for example, for each chocolate bar sold for $2.50, Fairtrade earns about six cents of the fair trade premium. West African cocoa farmers, on the other hand, earn only 2.5 cents.

http://africasacountry.com/2012/12/10/the-fairtrade-facade/