Sliplining, also called insertion renewal or relining, employs sections of polyethylene (PE) pipe that are joined by heat fusion into one continuous length as they are fed into the old sewer pipe. Existing building connections are then rehabilitated as required and joined to the new PE liner by heat-fused or mechanically attached saddles. The resulting system is a watertight, smooth bore line approximately ten percent smaller than the old, decaying line, but with a much lower friction factor. The application of the technique in two towns of New York, namely Utica and Farmington, are cited as examples, along with resulting economic benefits. Other techniques are also mentioned but briefly.