In this revelatory, authoritative portrait of Donald J. Trump and the toxic family that made him, Mary L. Trump, a trained clinical psychologist and Donald’s only niece, shines a bright light on the dark history of their family in order to explain how her uncle became the man who now threatens the world’s health, economic security, and social fabric.

Numerous pundits, armchair psychologists, and journalists have sought to parse Donald J. Trump’s lethal flaws. Mary L. Trump has the education, insight, and intimate familiarity needed to reveal what makes Donald, and the rest of her clan, tick. She alone can recount this unnerving saga, not just because of her insider’s perspective but also because she is the only Trump willing to tell the truth about one of the world’s most powerful and dysfunctional families.