Thought Provoking and Informative. I consider myself a well read guy, a guy that has thought through a lot of problems and who generally knows a lot about a lot. Admittedly, I did *not* know much about toilets and related plumbing, though I had read bits and pieces in other books. (Such as a more in-depth look at John Snow and his work during the 19th century London cholera outbreak in Dierdre Mask's The Address Book.) But I had never read up on the general history of toilets - apparently because there are scant details about historical toileting beyond the last couple of hundred years or so - much less the bleeding edge issues and technologies of this field. And that is exactly what Wald provides here, a look at everything from the history to almost to-the-day bleeding edge issues, including the Great Toilet Paper Outage of 2020 during the early stages of the coronavirus pandemic. Very well written and mostly reasonably documented (about 15% or so is bibliography), this truly is a fascinating read. Very much recommended.