Indoor microbiology was a notable presence at last week’s ISME Congress in Copenhagen, Denmark. The biennial summit of the world’s microbial ecologists featured research from a growing number of indoor microbiology groups, including the BioBE Center. Tim O’Connor presented the Center’s latest results on the microbial biogeography of the Lillis Business Complex (“Building-scale biogeography of indoor bacteria”). As revealed by microbial DNA in settled dust, everything is not everywhere within buildings; rather, architectural parameters and human use produce spatially structured bacterial communities. Other indoor microbiome highlights included a round-table discussion entitled “Indoor Microbiology: new molecular-based insights and management strategies,” which promoted the field’s recent advances and open questions. We look forward to even more great built-environment microbiology at the next ISME Congress in Seoul.