Over the last decade, Europe has seen a marked increase in the use of the polygraph for the detection of deception. Belgium and Finland nowadays regularly use polygraph tests in criminal investigations, and the United Kingdom and the Netherlands have adopted its use in the treatment and monitoring of sex offenders. Still, the use of the polygraph for the detection of deception has been debated in the scientific literature for ages. In this article, we highlight the promises and perils of the use of the polygraph for the detection of deception.