It is widely accepted that traumatic experiences during critical stages of child development can predispose in clinical conditions such as anxiety, depression, post traumatic stress disorder symptoms, personality disorder etc. The research about the developmental implications of trauma on the biological systems responsible for the modulation of stress is on its early stages. The involvement of endocrinological and neurochemical changes has long been described. Recently, neuroimmaging as well as molecular genetics findings have been reported. The exploration and understanding of the above biological mechanisms may lead to preventive strategies or more effective treatment for children who have fallen victims of abuse, neglect or trauma.