In 2017, the "Know Thy Star, Know Thy Planet" conference held in Pasadena, CA focused on understanding how stars affected our ability to discover and do intial characterization of exoplanets.  Over the past seven years since that conference, the limits of exoplanet discovery and the field of exoplanet characterization have changed dramatically, with great strides made in the community to understand and account for, at any even more precise and complex levels, the characteristics and effects of the stellar hosts.  Know Thy Star 2 focuses on the effects that stars have in limiting our ability to determine planetary masses, orbits, bulk compositions, and atmospheric abundances - and the state of the art knowledge and techniques that have been developed to mitigate the stellar effects.  By Knowing thy Star, we can better Know Thy Planet!