Summarizes the main cable monitoring techniques which are currently being assessed worldwide. These techniques are primarily aimed at monitoring degradation of low-voltage cables. Most of the methods are at the development stage and require more in-plant evaluation before they could be recommended as standard techniques. The advantages and disadvantages of each method, and its current state of development, are outlined in the following clauses. The main technical changes with regard to the previous edition are as follows: a) as there have been technical advances in established test methods and newer methods have become available, several additions have been made to the techniques available in Clause 5; b) some of the techniques listed in the previous edition were found to be either unsuitable for use as cable monitoring methods in plants, or less sensitive to radiation ageing than other methods; these techniques have now been removed; c) a list of abbreviations and their meanings has been added.