Metal halide perovskites have attracted enormous attention in the scientific community in recent years. This attention has been drawn by breakthroughs in perovskite optoelectronics, mainly in photovoltaics and LEDs. Although there has been great progress in their use in optoelectronics, fundamentally understanding this class of materials is still challenging, in particular the interplay of several physical and chemical processes. Many fundamental questions are left unanswered, such as what makes them unique/excellent semiconductors; how to tune their optoelectronic properties; why some compositions are more stable than others; the consequence of their chemical instability on their optoelectronic properties; and how to stabilize them. We, the Computational Materials Physics Group, focus on addressing such questions using computer simulations and theoretical analyses based on the laws of Quantum Mechanics. In this talk, I will highlight our recent progress and give an outlook of our next challenges with a discussion of future strategy along this line of research.