This article assesses the latest edition of the Ministry of Defence’s (MoD) joint space doctrine, the second edition of which was published in December 2017, and considers its convergence with and divergence from US doctrine. The increasing maturation of space technology may pose some challenges to the RAF’s status as the lead military space organisation in the MoD as the service heads into its second century. Overall, however, Bleddyn E Bowen argues that this doctrine places a firm intellectual foundation for the growth of space power in both the RAF and the MoD as a whole.