It seems that the decade of 2020 is going to be focused on clean air, whether it is on the street or inside of a building. Given what we know about how viruses spread and especially so about Covid-19, the importance of clean air has never been greater. Since the start of 2020 and going into 2021, we have seen a strong uptick in requests for CFD engineering services to improve air quality inside and outside of buildings. It seems obvious, but to ensure clean air inside the building one starts from the outside to keep exhaust out and clean air in. Our CFD consulting projects have ranged from hospitals, data centers, factories, large parking garages to office towers. In every case, the requirement was to digital prototype the air quality inside these buildings. We also get involved in combustion engineering to maximize the efficiency of boilers. This is often the most challenging work to optimize the combustion process to reduce air-borne particulate. All-in-all, we do live in a cleaner world than that chronicled by Dickens in the early 1800’s, where the streets of London were often night-like at noon, and I’m sure that in the following years we will see continued improvement in the air quality that we all breath.