EEG recording has been widely used in a variety of applications, including sleep studies, mental health monitoring, brain-computer interfaces (BCIs), etc. However, mainstream clinical recording systems are still tethered with wet electrodes that require special preparation, limiting the setup to well-equipped labs and preventing the collection of longitudinal data. In this article, we summarize the special characteristics of EEG signals and review key circuit design techniques in EEG signal acquisition and data telemetry. With careful system optimization, a wireless distributed recording setup is possible for nonintrusive EEG data collection, which will enable long-term mental health monitoring and other important applications. © 2009-2012 IEEE.