The fixed assetis of central importance to the publicutility and disposal industry. It often covers values above 95 % of the total assets.Within the frame of construction works on the fixed asset it is to be decided whether these are to be classed as installation costs that can or must be treated as addition to assets, or whether they have to be handled as running maintenance expenditure. This question becomes even more relevant once the disposal facilities have largely been completed. The decision taken has an immediate effect on the operating result, and thus essentially influences the charges for waste disposal, since installation costs will only affect the current year's result by their depreciation amount, i. e. in the range of2 % to 10 %, while maintenance expenditure have a 100 % impact on the current year's result. This Advisory Leaflet was compiled by the ATV-DVWK-Working Group "Anlagevermögen -Erfassung und Fortschreibung" ("Fixed Assets-Assessment and Extrapolation"). It shall assist the operators of public utility and disposal facilities when seeking an appropriate decision. This Advisory Leaflet also provides information about the particularities of inliner procedures and burstlining procedures in connection with the redevelopment of pipeline networks. This Advisory Leaflet is to be considered supplementary to theStandard ATV-A 133 "Recording, Assessment and Extrapolation of Assets of local Drainage Facilities".