Many hundreds of subsea wells are currently in service worldwide. Subsea wells may be installed individually, in clusters, or on a template where the reservoir fluids from all the wells are channeled to a manifold that is tied back to a host platform. A simple template arrangement is shown in Figure 1. Often wellheads and wet trees are designed as "diverless" and more recently "guidelineless" because they can be installed, maintained, and repaired either by remote control using equipment that does not need guidelines or tools that are wire guided from a vessel. Figure 1 shows a single-well diverless subsea production system.