In the second decade of the 21st century, the Philippine terrorist organisation the Abu Sayyaf, predominately domiciled in the southern Philippines, added a new dimension to their kidnap-for ransom enterprise – piracy. Accompanied by kidnap-for-ransom as opposed to traditional piracy which, in the main, this involved the robbery of an ocean-going vessel’s crew, cargo, or even the vessel itself. The Abu Sayyaf has been in existence in some form or another for over a quarter of a century in the greater Mindanao region of the southern Philippines. Originally formed with the intention of creating an independent Muslim State in the southern Philippines, it has degenerated into a number of sub-groups whose sole endeavour is now kidnap-for-profit, accompanied in many instances – if a ransom is not paid – by beheading of the kidnap victims. Flush with funds, the various groups were able to purchase small fast-moving vessels and embarked on piracy in the greater Sulu and Celebes Seas region. This publication focuses on the "explosion" of Abu Sayyaf piracy in the region in 2016 and 2017.