Interface Region Imaging Spectrograph (IRIS) fills a crucial gap in our ability to advance Sun-Earth connection studies by tracing the flow of energy and plasma into the corona and heliosphere for which no suitable observations exist. IRIS obtains high, resolution UV spectra and images of the sun's chromosphere, specifically on the non-thermal energy that creates the Corona and the Solar Wind; i.e., Space Weather. IRIS is a Principal Investigator (PI) led Small Explorer Mission; PI is Alan Title located at Lockheed Martin Advanced Technology Center, Solar and Astrophysics Laboratory.