The workshop series began in 2003 and was initially held in the Santa Fe Institute (SFI), New Mexico for the first five years. It was the result of a consultation with the faculty and Business Network at SFI on what technical domain might best benefit from a Complex Systems perspective. After many coffees it was agreed that an obvious field would be to analyse cyber security from this viewpoint. The resulting heated workshop discussions rapidly confirmed that indeed, cyber security is a very complex and highly adaptive problem domain. Since 2007 the event has been held in the UK.