Abstract: A catheter connection system is defined by a rigid, tubular stem attached at a proximal end thereof to a medical device. The stem has a plurality of engagement barbs encircling and radially, outwardly extending on an exterior surface of the stem. The engagement barbs can be configured having a variety of different sizes and positions. A locking barb also encircles and radially, outwardly extends on the surface of the stem between the medical device and the engagement barbs. A variety of fastening assemblies are provided for inwardly compressing a portion of a body wall of a selected catheter against the engagement barbs on the stem, when the stem is received in the lumen of the selected catheter. The fastening assemblies create a mechanical joinder and liquid-tight seal between the selected catheter and the stem. The selected catheter can be chosen from one of three or more catheters each having a combination of size and material composition distinct from the other of the catheters.