Total column ozone (TCO) data from multiple satellite-based instruments have been combined to create a single near-global daily time series of ozone fields at 1.25degree longitude by 1degree latitude spanning the period 31 October 1978 to 31 December 2016. Comparisons against TCO measurements from the ground-based Dobson and Brewer spectrophotometer networks are used to remove offsets and drifts against the ground-based measurements in a subset of the satellite-based instruments. The corrected subset is then used as a basis for homogenizing the remaining data sets. The intention is that this data set serves as a climate data record for TCO and, to this end, the requirements for constructing climate data records, as detailed by GCOS (Global Climate Observing System) have been followed as closely as possible. The construction of this database improves on earlier versions of the database maintained first by the National Institute of Water and Atmospheric Research (NIWA) and now by Bodeker Scientific (BS). The new version includes a wider range of satellite-based instruments, uses updated versions of the source satellite data, extends the period covered, uses improved statistical methods to model the difference fields when homogenizing the data sets, and, perhaps most importantly, robustly tracks uncertainties from the source data sets through to the final climate data record which is now accompanied by associated uncertainty fields. The data are available in daily, monthly or yearly resolution. Please email greg@bodekerscientific.com and let us know which data set you downloaded and what your intended purpose for the use of the data is. You will then receive updates if an improved version becomes available.