In the author's 1955 paper an attempt was made to divide mortality into six component parts, one being the rate of senescent deaths, the others the respective rates of different types of anticipated deaths, the distinction between senescent and anticipated deaths having previously been drawn by Clarke in his centenary paper. At the same time the author advocated an investigation into the mortality of assured lives by cause of death, one of the uses of such investigation being the continuous availability of a comparison between assured lives' mortality at different durations and national mortality. The Joint Mortality Investigation Committee is indeed now conducting such an investigation, starting with the year of experience 1964 and, though no report on this investigation has yet been published, it is reasonable to presume that the Committee's first such report will become available in the fairly near future.