The earliest measure of putting was a simple counting of the number of putts in a round. A more refined measure of putting called 'strokes gained' was introduced in Broadie (2008) and used by Fearing, Acimovic and Graves (2011) to rank putters on the PGA Tour. Strokes gained putting takes into account putt difficulty as a function of putt distance in order to quantify and rank putting performance. In this paper, we green contours and simulated putt trajectories to more accurately quantify putt difficulty and rank putting performance. (Joint work with Dongwook Shin.)