Sheryl Sandberg opens by examining both internal psychological barriers and external structural obstacles affecting women's professional advancement, arguing genuine progress requires addressing both dimensions together rather than focusing exclusively on either alone.

Why addressing both dimensions together matters:

• Focusing exclusively on internal psychological barriers risks inappropriately placing full responsibility on individual women while ignoring genuine external structural obstacles
• Focusing exclusively on external structural obstacles, without addressing internal psychological barriers individual women might also address, provides incomplete practical guidance
• This opening establishes the book's foundational dual-focus framework, motivating its subsequent detailed examination of both dimensions

This opening establishes the book's foundational framework, addressing both internal psychological barriers and external structural obstacles together as affecting women's professional advancement.