It is likely that most researchers and practitioners operating within (that is, 'with' and 'in') complex technological systems would agree with the observation that humans contribute positively to mitigating risk. Indeed, there is a growing consensus that researching error alone cannot help us to fully understand how reliability in systems is accomplished. The contributors in this book show how such reliability is created in the ways in which humans work within their systems, positively taking into account the tallibility of those systems. This book is, therefore, about shedding light into the ways in which reliability is accomplished most of the time, despite imperfect systems, technologies and organizational procedures.