In the late 1990s, the rate of youth offenses in the U.K. continued to increase since the youth justice system had been adopted. The U.K. admitted the limitation of the paternalistic approach to youth and enhanced the protection of youth rights, diversion, and the youth welfare system. Statistics show a significant reduction in youth offense rates since the mid-2000s, but the proportion of indictable offenses has remained steady for decades. The CFOS(Children First Offense Second) Model, which positively implements youth participation under the Convention of the Rights of the Child Art. 12, was proposed to solve the fundamental youth offense problems. CFOS Model asserts that the power of control not to commit crimes can be developed when youths experience their opinion to be applied to youth practice. The participatory youth practice goes further, making youths decide the procedure and programs in the youth justice system. CFOS Model and the participatory youth practice are still experimental but have significant implications for our youth justice system.