BIOSENSOR SENSITIVITIES WERE ENHANCED SUFFICIENTLY TO ENABLE DETECTIONS OF DYNAMITE VAPORS FROM VARIOUS PACKAGE CONFIGURATIONS (LUGGAGE, CARTONS). THE HEROIN VAPORS WERE DETECTABLE FROM CUTTING ROOMS AND WALLS WHICH WERE PRIMARY PROGRAM OBJECTIVES. PRIOR TO THIS CONTRACT, IT WAS ONLY POSSIBLE TO DETECT HEROIN AND DYNAMITE VAPORS FROM A PLASTIC CONTAINER THROUGH ACCESS HOLES IN THE CONTAINER. BIOSENSORS SENSITIVE TO MARIJUANA AND COCAINE VAPORS WERE ALSO DEVELOPED, ALTHOUGH NOT TO THE EXTENT OF BEING USED FOR FIELD DETECTIONS. IN CONJUNCTION WITH THE BIOSENSOR SENSITIVITY ENHANCEMENT, ENGINEERING ADVANCES CONTRIBUTED TO THE DEVELOPMENT OF AN OPERATIONAL PROTOTYPE FIELD SYSTEM. THE PROTOTYPE DETECTOR UNITS ARE PORTABLE AND CAN BE OPERATED FROM AC OR DC POWER. (AUTHOR ABSTRACT)