We are guest editing a special issue of “Halide Perovskites for Photonics and Optoelectronics” in Optical Materials Express together with Prof. Xiwen Gong @ University of Michigan, USA; Prof. Sergey Makarov @ ITMO University, Russia; Prof. Barry Rand @ Princeton University, USA; and Prof. Yongsheng Zhao @ Institute of Chemistry, CAS, China. Looking forward to your submissions!