, 11 January 2012 (UTC)
There is a vast body of work on this topic, called motivation crowding theory. The great news is that while the authorities on the subject have always said that monetary rewards can strengthen intrinsic motivation under some conditions, recent work suggests that those conditions have become far more well understood. For example:
 "intrinsic interest is actually higher under [pay for individual performance]"  Fang, M. and Gerhart, B. (2011) "Does pay for performance diminish intrinsic interest?" International Journal of Human Resource Management 
 "Median FRT [response time] was reduced from 90 to 70 days, a 22% reduction in the presence of payments. With payments, only 1% of the FRTs exceeded six months; without payments, 16% of the FRTs exceeded six months."  Thompson, G.D., et al. (2010) "Does Paying Referees Expedite Reviews? Results of a Natural Experiment" Economic Journal 76(3):678-92
 "monetary payments as well as intrinsic motivation have roles in the real-life decision to supply volunteer work, but monetary rewards do not crowd out intrinsic motivation"  Fiorillo, D. (2011) "Do monetary rewards crowding intrinsic motivations of volunteers? Some empirical evidence for Italian volunteers" Annals of Public and Cooperative Economics 82(2):139–65
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