The hottest field in the world of advanced materials today is 3D printing. But this has been a long time coming. Hideo Kodama of Nagoya Municipal Industrial Research first developed additive manufacturing equipment and materials in1981. This original work closely resembles the stereolithography technique pioneered by Charles Hull that remains a dominant technique today. Despite the promising future at the time of this original work, it wasn’t until 27 years later, in 2008, that the additive manufacturing industry finally surpassed one billion dollars in revenue, a key threshold in becoming mainstream. Borrowing from Silicon Valley, I’ll use the term “revenue unicorn” for this milestone. Since that time, there has been no looking back.