(Note: This interview first aired back in November.) Our guest is Joseph G. Allen, the Director of Harvard's Healthy Buildings Program and an Associate Professor at the Harvard T.H. Chan School of Public Health. Allen is a noted forensic investigator of so-called "sick buildings" -- and his landmark book, "Healthy Buildings" (which he cowrote with John D. Macomber), has recently been reissued in a new, post-COVID edition. Per Fortune Magazine: "This exposé of the widespread under-ventilation and pollution inside modern buildings arrived just as shared indoor space became truly deadly. Though there's now light at the end of the COVID-19 tunnel, [this book's] insights and guidelines for improving indoor air quality should play a huge role in post-pandemic reforms."