The generation of a stochastic gravitational wave background is a key prediction of cosmological theories of inflation. At large angular scales, these gravitational waves would imprint a unique “B-mode” polarization pattern in the Cosmic Microwave Background (CMB), providing a new window into the physics of the early universe. SPIDER is a balloon-borne telescope that has been uniquely optimized to search for this inflationary signal in the CMB over the course of two Antarctic flights. The first of these flights took place in 2015, and I will present an overview of flight performance and preliminary data. I will also discuss preparations for the second flight, which is currently scheduled for December 2019. This flight will include a higher frequency channel to measure galactic foregrounds.