Editorial introducing double special issue of Journal of Mathematics and the Arts, vol. 12, issues 2-3 (2018), honouring the memory of Reza Sarhangi (1952-2016). Editorial highlights the achievements of Reza Sarhangi in founding the Bridges Conference and other organizations that seek to promote intersectionality in mathematic and the arts, and his scholarship on tilings, modularity, and patterns in Persian art. The first cluster of articles by colleagues from around the world focuses on tilings, tessellations, and patterns in the plane; the second cluster offers different perspectives on spherical geometry.