Book Overview 1. Entrepreneurs and Startups 2. Doctors, Nurses, and Health Professionals 3. Pharma, Biotech, Device Companies 4. Patients and Consumers 5. Employers, Insurers, Regulators 6. Gadgets, Apps, Technology 7. Behavior, Design, and Translation 8. Big Data, Measurement, and Metrics 9. VCs and Other Investors 10. Innovation --- Health matters. "When you have your health, you have everything," wrote memoirist Augusten Burroughs. "When you do not have your health, nothing else matters at all." Health can also be very expensive, and reducing costs isn't easy, since as Stanford health policy expert Victor Fuchs famously observed, "Every dollar of waste is income to some individual or organization." One key challenge healthcare faces today is figuring out how to maintain health and deliver better care for patients while somehow keeping in check the overall costs associated with these activities. The good news is that there is now the massive potential for healthcare transformation. Data-driven analysis has called into question many traditional healthcare assumptions, and permits us to view the challenges in a fresh light. For instance, there seems to be little correlation between healthcare cost and quality-and great care can be delivered at lower cost if we can improve the alignment of incentives among patients, payers, and providers. Key drivers of healthcare change are the intense economic pressure of healthcare costs, the impact-to be determined-associated with the implementation of the Affordable Care Act, and the advent of inexpensive and widely accessible technologies; together these have created a platform for industry transformation the likes of which has not been seen since the dawn of modern surgery. And it's about time. Technology has been used to optimize and redefine virtually every key industry except healthcare. Manufacturing has gone from human assembly lines to robotics; banking has gone from tellers to home banking; travel has gone from agents with brochures to Travelocity; and yet the practice of medicine, in many ways, hasn't changed in decades. Many of today's most passionate entrepreneurs are trying to bring the dazzle and real promise of technology innovation to the challenges of healthcare, resulting in an explosion of companies focused on everything from wearable sensors and weight-loss apps to big data analytics and GPS-tagged hospital equipment-the "internet of things." These emerging tools and promising technologies-which collectively comprise "digital health"-offer a promising path forward, and entrepreneurs and innovators are forging forward seeking to make a real difference in a field which we all need but which is sorely in need of its own tender loving care if it is to flourish in tomorrow's world. As Hippocrates once said, "Healing is a matter of time, but it is sometimes also a matter of opportunity." And technology-if judiciously applied-may be just the tonic to help reinvigorate the health of our healthcare industry. The key challenge faced by would-be disruptive technologists is not only recognizing potentially useful analogs from other industries, but also understanding the ways in which health remains fundamentally different. Amid the clamor to disrupt healthcare, we should also take care to preserve and augment what may be right about medicine-the doctor/patient relationship for example, or the drive of inquisitive physicians, especially within academic centers, to continuously push and challenge the limits of what is known and what is possible. In Tech Tonics-a distillation of our writing and thinking over the last several years-we introduce the reader to the fascinating digital health space, including a ground-level view of the landscape, the structural challenges, the players, and the progress.