The collection, analysis and utilization of digital information based on our clicks, swipes, likes, purchases, movements, behaviors and interests are now part of everyday life. While individuals become increasingly transparent, companies take control of the recorded data in an often nontransparent and unregulated way. Wolfie Christl and Sarah Spiekermann explain how today's networks of corporate surveillance are constantly tracking, profiling, categorizing, rating and affecting the lives of billions - across platforms, devices and life contexts. Based on detailed examples their comprehensive report answers the following questions:

. Who are the players in today's personal data business? How do online platforms, tech companies and data brokers really collect, share and make use of personal information?
. Which data is recorded by smartphones, fitness trackers, e-readers, smart TVs, connected thermostats and cars? Will the Internet of Things lead to ubiquitous surveillance?
. What can be inferred from our purchases, calls, messages, website visits, web searches and likes? How is Big Data analytics already used in fields such as marketing, retail, insurance, finance, healthcare and work to treat us differently?
. What are the societal and ethical implications of these practices?
. How can we move forward?

Their investigation not only exposes the full degree and scale of today's personal data business, but also shows how algorithmic decisions on people may lead to discrimination, exclusion and other social implications. Followed by an ethical reflection on personal data markets the authors present a selection of recommended actions.