Particle production and solids processing are essential components of the contemporary process industries. Crystalline solids represent a large and important segment of this manufacturing sector. Chemical engineers, especially in the United States, have historically abandoned this subject, leaving it to pharmacists, physical chemists, material scientists, geologists, and other disciplines. In fact, crystalline solids have become the lost phase of the chemical engineering curriculum. Both the subject and the community are large; it is easy to assemble over 300 delegates at crystallization conferences, and there are many journals and books devoted to crystals. In my view this is a missed opportunity for chemical engineers, and also a missed opportunity for the field of crystal engineering. Crystal engineering has evolved into a mostly descriptive field (the materials science focus) with only a small component concerned with quantitative aspects. Chemical engineers are uniquely positioned to make major quantitative contributions to crystal engineering like they did for industrial chemistry and fluid-phase processes during the twentieth century. Moreover, crystalline solid products offer an excellent platform for advancing the field of integrated product and process design. Changes to the chemical engineering curriculum are recommended in order to provide graduates with the education necessary to compete for jobs in this manufacturing sector.