Semiconductor photonics at the chip-scale is reviewed, with revenue forecasts given for six key markets. Forecasts are disaggregated by specific applications, material platforms (including silicon and indium phosphide), and geography. We show that the semiconductor photonics industry will not reach saturation by 2033, and is growing at an impressive rate. Semiconductor photonics is the best candidate for achieving increasingly high data rate transmissions, over increasingly long distances.