Crowdsourcing is often used to foster innovation, but in practice unlocking the wisdom of the crowd is easier said than done. Firms can be overwhelmed by bad or useless ideas, which can clog up the process and even lead a company astray. Many crowdsourcing campaigns offer prizes for winning ideas, but determining the optimal type (cash or non-cash) and size of the reward is a difficult task. There is also evidence that firms resist ideas, no matter how worthy, that weren’t invented internally.