Abstract: This month we are happy to present the annual Presidential theme issue, intended to coincide with the Presidential theme of the 2018 AAAAI/WAO Joint Congress in Orlando, Florida, bringing our readers 3 review articles on the topic of pollution and its effects on allergy and immunology.As depicted on this month's cover, indoor pollution affects the full spectrum of humanity, from a household struggling with thick and toxic smoke given by a biofuel cook stove in the developing world, to the myriad indoor pollutants found in homes in the US and Western Europe.These pollutants have plagued the globe's citizens for generations but only in recent decades have researchers been able to quantify some of the ill effects.It is our hope that focusing some additional attention in this issue will help allergist/immunologists worldwide to find ways to improve the health of patients suffering from these effects.The cover is also intended to convey that one cannot look at indoor pollution in isolation, as it is closely related to outdoor pollution as well.This issue's Clinical Review by Carlsten and colleagues (p 833) details the spectrum and specifics of the inflammatory effects of indoor and outdoor particulate matter.The Mechanisms review by Cecchi et al (p 846) covers asthma and the environment.A theme editorial from AAAAI President David B. Peden (p 878) ties the issues together.Outside of the theme articles, a Current Perspectives by Bag ˘ci and colleagues (p 858) looks at new research on IL-31.A timely Paradigms and Perspectives by Javier Chinen (p 876) covers the impact on clinicians and researchers brought by natural disasters.We are also very pleased to present an editorial by K. Frank Austen (880) on the ever important topic of mentorship.