A method of and apparatus for assessing the condition of a fluid conduit. The method comprises providing a measurement apparatus comprising a measurement region in fluid communication with the fluid conduit. The measurement apparatus is operable to measure at least one of pressure and flowrate in the measurement region. A pressure surge is effected or generated to propagate in the fluid conduit, and at least one of a pressure response or a flowrate response from the fluid conduit is measured. From a pressure data set and a flowrate data set, a data set representative of the cross sectional area along the fluid conduit is determined. This enables average or over all area profiles along long fluid pipelines to be deduced.