The present investigation was made from a descriptive-explorative approach and its aim was to know the perceptions of change of professionals who work with teenagers under custodial sentences. The sample consisted of eight professionals, who through a semi structured interview gave his findings on four analysis axes. The main results showed that professionals perceive change as an exceptional process in which several factors converge, including criminal action and deprivation of freedom. In conclusion, it can be mentioned the need for specialization in professionals who work with high complexity population and the development of strategies for adopting an active role in the processes of change of adolescents.