To share or not to share: that is not the question.

There is an increasing awareness of the power of integrating multiple sources of data to accelerate biomedical discoveries. Some even argue that it is unethical not to share data that could be used for the public good. However, the challenges involved in sharing clinical and biomedical data are seldom discussed. I briefly review some of these challenges and provide an overview of how they are being addressed by the scientific community.