Use of Weapons is a science fiction novel by Scottish writer Iain M. Banks, first published in 1990 as the third novel in the Culture series.
The narrative takes the form of a fractured biography of a man called Cheradenine Zakalwe, who was born outside of the Culture but was recruited into it by Special Circumstances agent Diziet Sma to work as an operative intervening in less advanced civilizations. The novel recounts several of these interventions and Zakalwe's attempts to come to terms with his own past.
The book is made up of two narrative streams, interwoven in alternating chapters. The numbers of the chapters indicate which stream they belong to: one stream is numbered forward in words (One, Two ...), while the other is numbered in reverse with Roman numerals (XIII, XII ...). The story told by the former moves forward chronologically (as the numbers suggest) and tells a self-contained story, while in the latter is written in reverse chronology with each chapter successively earlier in Zakalwe's life. Further complicating this structure is a prologue and epilogue set shortly after the events of the main narrative, and many flashbacks within the chapters.