The chapter considers the range of features that enable investigators to describe a killing as ‘sexual’, such as clothes removed, objects inserted into the body and presence of seminal fluids on the body. Some killing done in association with sexual behaviour is not motivated by lust. For example, it might represent an attempt to avoid capture following a sexual assault or the accidental result of choking. Some killers reach orgasm from simply cutting a victim, while others (e.g. David Berkowitz) are sexually aroused by shooting a courting couple. The chapter describes a number of common features of a ‘composite killer’, such as cruelty to animals and voyeurism. Various ruses might be used in order to get a victim in the situation where he or she can be killed, such as offering a lift or seeking help. However, the most common method appears to be to engage the services of a sex worker.