“…Aggression is reported as a frequent indication for psychiatric hospitalization (Rice, Woolston, Stewart, Kerker, & Horwitz, 2002; Ros, van der Helm, Wissink, Stams, & Schaftenaar, 2013), and as such becomes part of daily life in residential psychiatric units and forensic treatment units for children and adolescents (Crespi, 1990; Day, Franklin, & Marshall, 1998; Kaltiala-Heino, Berg, Selander, Työläjärvi, & Kahila, 2007; Tremmery et al, 2014; Tremmery, de Decker, De Hert, De Varé, & Danckaerts, 2012). Vulnerable children and adolescents, with commonly complex psychiatric disorders are almost daily exposed to aggressive situations, either as victim or as witness.…”