Sandberg, then Facebook's chief operating officer, argues that women's underrepresentation in senior positions results from both external barriers and from internal patterns that women can address directly, and she concentrates on the second while acknowledging the first.
Her specific claims include that women systematically underestimate their own capability and apply for roles only when they meet all stated requirements while men apply meeting a fraction; that women are penalised socially for the assertiveness that produces advancement, which is a documented likeability and success trade-off that men do not face; that women begin withdrawing from career advancement in anticipation of children years before having them, which she calls leaving before you leave; that the choice of a partner is the most consequential career decision a woman makes, since domestic labour distribution determines what is possible; and that mentorship should be earned through performance rather than requested directly.
She draws on research including the Heidi and Howard case study, in which identical résumés with different names produced different assessments of likeability, and on data about negotiation outcomes and about domestic labour distribution.
The book received substantial criticism for concentrating on individual behaviour rather than on structural and policy change, for generalising from an unusually privileged position, and for placing responsibility on women for a problem created by institutions. bell hooks and others made this case forcefully. Sandberg addressed some of it afterwards, particularly regarding single parents and women without resources. The research findings on the likeability penalty and on self-assessment are well supported.
Women navigating corporate advancement and managers examining their own assessment practices, with the structural criticisms understood.
Chosen by shared topics, the entries that hold them, and the people who recommended both.

