In this article I argue that the global biosecurity project that arose out of the events of the SARS epidemic of 2003 created a new balance of secrecy and transparency within the public health arm of the Chinese state. In an effort to meet national and international demands for greater transparency in support of a “common good,” local public health officials engaged in what I call hypertransparency. This hypertransparency took two forms: the real-time online sharing of disease incidence data within the public health bureaucracy, and the over-performance of disease fighting strategies in front of a wider local and global public. Because local Chinese officials interpreted the “common good” differently from their international partners, neither of these efforts succeeded in erasing the crucial role that local officials continued to play in determining what should and should not be shared, and with whom. Secrecy continued to be an important component of China’s securitization efforts, with hypertransparency ultimately concealing more than it revealed.