Hunting black holes with Gaia

We predict the number of black holes with stellar companions that are potentially detectable with Gaia astrometry over the course of its 5-yr mission. Our model estimates that nearly 2x10(5) astrometric binaries hosting black holes and stellar companions brighter than Gaia's detection threshold, G similar to 20, should be discovered with 5 sigma sensitivity. Among these detectable binaries, systems with longer orbital periods are favoured, and black hole and stellar companion masses in the range M-BH similar to 6-10 M-circle dot and M-* similar to 1-2 M-circle dot, respectively, are expected to dominate.