The controversy between nature vs. nurture, or are criminals born or made has been debated between experts over years. The conclusion is unclear and is intangible, but there are several theories in which leads oneself to an answer. Researching both sides of the debate, criminals are born and made, they are essentially themselves because of nature and nurture. Serial killers do these crimes primarily due to nature and nurture. This essay will prove that Serial killers commit these crimes due to nature and nurture, using examples such as; Science experiments, the effects of nurture on a baby, and profiling the characteristics of Serial killers.