I have been thinking about absolute flux calibrations for over 50 years, since I was assigned to read a paper in Vol. 1 of JSQRT as an undergrad in 1965; and one of my tasks in grad school in 1967 was to calibrate a spectrometer for absolute flux measurements. From 1970 to 1982 I did absolute flux calibrations of several rocket experiments, including one to measure the absolute UV flux of Vega in 1972. I was in charge of absolute flux calibration of IUE (1979-1982) and the UIT payload on the Spacelab programs Astro 1 and 2. I have been Calibration Scientist at the STScI since 1982. The HST instruments for which I have done calibrations include FOS, STIS, NICMOS, ACS, and WFC3.