Abstract: There is provided a process for stabilizing additive concentrates comprising or consisting of one or more additives in dialkylsilanol terminated polydiorganosiloxane polymers for use in condensation curable organosiloxane compositions. Processes for making condensation curable organosiloxane compositions incorporating the additive concentrates as well as the use of the stabilized additive concentrates in condensation cure organosiloxane compositions are also described. The stabilizer used is a polydialkylsiloxane having the general formula: R33—Si—O—((R2)2SiO)d—Si—R33 where R2 is an alkyl or phenyl group, each R3 group may be the same or different and are selected from R2 alkenyl or alkynyl groups and the average value of d is between 7 and 20, in an amount of from 0.5 to 5 wt. % of the composition.