A process to produce paraffinic products for use as or conversion to oilfield hydrocarbons and to produce lubricant base oils, the process including separating a Fischer-Tropsch wax into a light fraction and a C 23 - C 50 intermediate fraction and a heavier fraction; hydro-isomerising the C 23 - C 50 intermediate fraction using a noble metal hydro-isomerisation catalyst on a SAPO-11, ZSM-22, ZSM-48, ZBM-30 or MCM-type support to provide a hydro-isomerised intermediate product and separating the hydro-isomerised intermediate product into two or more base oil fractions; and hydrocracking the heavier fraction such that at least 80% by mass of components of the heavier fraction boiling at 590°C or more is converted or cracked to boil at less than 590°C using a noble metal hydrocracking catalyst with a C 12 -C 22 selectivity of at least 75% to provide a cracked intermediate and separating the cracked intermediate in an atmospheric distillation column into at least a naphtha fraction, a heavier than naphtha paraffinic distillate fraction for use as or conversion to oilfield hydrocarbons, the distillate fraction comprising at least 50% by mass of hydrocarbons having chain lengths between 12 and 22 carbon atoms per molecule and the distillate fraction having a flash point above 60°C, achieved by setting a bottom cut-off point for the distillate fraction at around C 12 or higher in the atmospheric distillation column, and a bottoms fraction which is heavier than the paraffinic distillate fraction. separating a Fischer-Tropsch wax into a light fraction and a C 23 - C 50 intermediate fraction and a heavier fraction; hydro-isomerising the C 23 - C 50 intermediate fraction using a noble metal hydro-isomerisation catalyst on a SAPO-11, ZSM-22, ZSM-48, ZBM-30 or MCM-type support to provide a hydro-isomerised intermediate product and separating the hydro-isomerised intermediate product into two or more base oil fractions; and hydrocracking the heavier fraction such that at least 80% by mass of components of the heavier fraction boiling at 590°C or more is converted or cracked to boil at less than 590°C using a noble metal hydrocracking catalyst with a C 12 -C 22 selectivity of at least 75% to provide a cracked intermediate and separating the cracked intermediate in an atmospheric distillation column into at least a naphtha fraction, a heavier than naphtha paraffinic distillate fraction for use as or conversion to oilfield hydrocarbons, the distillate fraction comprising at least 50% by mass of hydrocarbons having chain lengths between 12 and 22 carbon atoms per molecule and the distillate fraction having a flash point above 60°C, achieved by setting a bottom cut-off point for the distillate fraction at around C 12 or higher in the atmospheric distillation column, and a bottoms fraction which is heavier than the paraffinic distillate fraction. a naphtha fraction, a heavier than naphtha paraffinic distillate fraction for use as or conversion to oilfield hydrocarbons, the distillate fraction comprising at least 50% by mass of hydrocarbons having chain lengths between 12 and 22 carbon atoms per molecule and the distillate fraction having a flash point above 60°C, achieved by setting a bottom cut-off point for the distillate fraction at around C 12 or higher in the atmospheric distillation column, and a bottoms fraction which is heavier than the paraffinic distillate fraction.