A secure passageway is described where a subject is required to pass through two or more chambers in order to travel between two areas, typically where one area is secure and the other is not. For a passageway including first and second chambers, three electronically controlled doorways are included: one between the two chambers; one between a first chamber and a first area; and one between the second chamber and a second area. Sensors are included to determine how many subjects have entered a chamber. Sensors are also included to determine if a subject represents a threat. Subjects determined to represent a threat may be detained or encouraged to reverse direction and exit the passageway through the door where they entered. When a subject is determined to represent a threat, an alarm is optionally sounded.