This commentary describes the author's experience working at two separate detention centres during her fellowship. She initially describes her experience performing forensic evaluations. The terms 'competency to stand trial' and 'criminal responsibility' are defined. It then describes the author's experience working in an inner city and suburban detention centre. The two environments and patient demographics are compared to a traditional inpatient or outpatient community setting. Fictional patient encounters, based on an amalgamation of actual patients, are discussed.