A trocar system comprising: a cannula having a working channel to receive surgical instruments therethrough and an outer surface; a stabilization seal coupled to the outer surface of the cannula, the stabilization seal comprising: an inflatable elongate tube having a proximal end, a distal end, an inner surface and an outer surface; a sealing cuff at the proximal end of the elongate tube; a central region of the elongate tube extending distally from the sealing cuff to the distal end; and a distal-end region of the elongate tube associated with the distal end; characterized in that a portion of the sealing cuff includes an integrally formed, substantially annular elastomeric seal portion that exhibits strong hoop force on the outer surface of the cannula to seal around the cannula in gas-tight arrangement, the stabilization seal includes means for coupling the distal end of the elongate tube to the outer surface of the cannula forming an inflatable region in a space from the outer surface of the cannula to the inner surface of the elongate tube, the central region of the stabilization seal has a first wall thickness, and the distal end region has a second wall thickness smaller than the wall first wall thickness such that the distal end region is expandable to form a balloon. a cannula having a working channel to receive surgical instruments therethrough and an outer surface; a stabilization seal coupled to the outer surface of the cannula, the stabilization seal comprising: an inflatable elongate tube having a proximal end, a distal end, an inner surface and an outer surface; a sealing cuff at the proximal end of the elongate tube; a central region of the elongate tube extending distally from the sealing cuff to the distal end; and a distal-end region of the elongate tube associated with the distal end; characterized in that a portion of the sealing cuff includes an integrally formed, substantially annular elastomeric seal portion that exhibits strong hoop force on the outer surface of the cannula to seal around the cannula in gas-tight arrangement, the stabilization seal includes means for coupling the distal end of the elongate tube to the outer surface of the cannula forming an inflatable region in a space from the outer surface of the cannula to the inner surface of the elongate tube, the central region of the stabilization seal has a first wall thickness, and the distal end region has a second wall thickness smaller than the wall first wall thickness such that the distal end region is expandable to form a balloon. an inflatable elongate tube having a proximal end, a distal end, an inner surface and an outer surface; a sealing cuff at the proximal end of the elongate tube; a central region of the elongate tube extending distally from the sealing cuff to the distal end; and a distal-end region of the elongate tube associated with the distal end; characterized in that a portion of the sealing cuff includes an integrally formed, substantially annular elastomeric seal portion that exhibits strong hoop force on the outer surface of the cannula to seal around the cannula in gas-tight arrangement, the stabilization seal includes means for coupling the distal end of the elongate tube to the outer surface of the cannula forming an inflatable region in a space from the outer surface of the cannula to the inner surface of the elongate tube, the central region of the stabilization seal has a first wall thickness, and the distal end region has a second wall thickness smaller than the wall first wall thickness such that the distal end region is expandable to form a balloon.