no one to say “Go away.” Hence I became more a constant interloper than an invited guest —something quite close to an actual fly on the wall—having accepted no rules nor having made any promises about what I might or might not write. Many of the accounts of what has happened in the Trump White House are in conflict with one another; many, in Trumpian fashion, are baldly untrue. Those conflicts, and that looseness with the truth, if not with reality itself, are an elemental thread of the book. Sometimes I have let the players offer their versions, in turn allowing the reader to judge them. In other instances I have, through a consistency in accounts and through sources I have come to trust, settled on a version of events I believe to be true. Some of my sources spoke to me on so-called deep background, a convention of contemporary political books that allows for a disembodied description of events provided by an unnamed witness to them. I have also relied on off-the-record interviews, allowing a source to provide a direct quote with the understanding that it was not for attribution. Other sources spoke to me with the understanding that the material in the interviews would not become public until the book came out. Finally, some sources spoke forthrightly on the record. At the same time, it is worth noting some of the journalistic conundrums that I faced when dealing with the Trump administration, many of them the result of the White House’s absence of official procedures and the lack of experience of its principals. These challenges have included dealing with off-the-record or deep-background material that was later casually put on the record; sources who provided accounts in confidence and subsequently shared them widely, as though liberated by their first utterances; a frequent inattention to setting any parameters on the use of a conversation; a source’s views being so well known and widely shared that it would be risible not to credit them; and the almost sami