Derived fromWireless Sensor Networks, Body Area Networks, comprise a wide range of typologies with sensor nodes placed on, close to, or implanted in the body that measure physiological signs.The availability of compact mobile computing devices makes it possible to integrate traditional healthcarewith newpowerfulmeans. Newparadigms in public health are arising from these developments, such as e-health and mHealth, and new converging applications can be envisioned. Physiological data acquisition provided by BANs may give care providers a unobtrusive real-time view on patient's health. On the other hand, the patient may be informed, assisted and even given the proper treatment by care providers. In this chapter, recent work on BANs focused on healthcare and mHealth is surveyed