The Ministry of Magic licenses Apparition. A witch or wizard must be 17 years old or older and have a licence to Apparate as a means of transportation in much the same way real-world governments require individuals to have a licence to drive a motor vehicle. Students at Hogwarts may attend Ministry-administered Apparition lessons during their sixth year, and take their examination once they turn seventeen. It is shown that although it is possible to Apparate without a licence, it is not usually done (unless in lessons) and is illegal. In "Deathly Hallows", Harry does not possess a licence, but since his Trace has been lifted, the Ministry is likely unaware that he does it.