  As the IoT becomes increasingly ubiquitous, concerns are being raised about
how IoT systems are being built and deployed. Connected devices will generate
vast quantities of data, which drive algorithmic systems and result in
real-world consequences. Things will go wrong, and when they do, how do we
identify what happened, why they happened, and who is responsible? Given the
complexity of such systems, where do we even begin?
  This chapter outlines aspects of accountability as they relate to IoT, in the
context of the increasingly interconnected and data-driven nature of such
systems. Specifically, we argue the urgent need for mechanisms - legal,
technical, and organisational - that facilitate the review of IoT systems. Such
mechanisms work to support accountability, by enabling the relevant
stakeholders to better understand, assess, interrogate and challenge the
connected environments that increasingly pervade our world.
