A method of joining articles (2) together with the aid of conductive polymer components. The conductive polymer components are neither heat-recoverable themselves nor fixed to heat-recoverable articles and preferably comprise a sintered ultra-high molecular weight polyethylene which undergoes a dimensional change when heat is generated within it. Specific components useful in joining or modifying articles such as pipes or cables are sealing strips (10), pressure access devices (60), and conductive polymer tapes (20).