The kinematic Sunyaev-Zel'dovich effect (kSZ) is a Doppler shift to the CMB signal imparted by the bulk motion of the hot gas in clusters of galaxies. Despite its small amplitude, the kSZ signal can be isolated using a differential statistic which probes the mean pairwise velocity of galaxy clusters. This pairwise kSZ signal is sensitive to a combination of cosmology and the baryonic physics of galaxy clusters, and may eventually be used to probe gravity at 100 Mpc scales. In this talk I will present a statistically significant (~4 sigma) detection of the pairwise kSZ signal by combining a cluster catalogue from the first year of Dark Energy Survey (DES) data with CMB temperature maps from the South Pole Telescope (SPT). This measurement is the first evidence of the kSZ using cluster redshifts derived from photometric data, and one of the first science results from the first year of DES data.