Watson has promoted education for girls, visiting Bangladesh and Zambia to do so. In July 2014, she was appointed as a UN Women Goodwill ambassador. In September that year, an admittedly nervous Watson delivered an address at UN Headquarters in New York City to launch the UN Women campaign HeForShe, which calls for men to advocate for gender equality. In that speech she said she began questioning gender-based assumptions at age eight when she was called "bossy" (a trait she has attributed to her being a "perfectionist") whilst boys were not, and at 14 when she was "sexualised by certain elements of the media". Watson's speech also called feminism "the belief that men and women should have equal rights and opportunities" and declared that the perception of "man-hating" is something that "has to stop". Watson later said she received threats within 12 hours of making the speech, which left her "raging. ... If they were trying to put me off [women's rights work], it did the opposite". In 2015, Malala Yousafzai told Watson she decided to call herself a feminist after hearing Watson's speech.
Also in September, Watson made her first country visit as a UN Women Goodwill Ambassador to Uruguay where she gave a speech highlighting the need for women's political participation. In December, the Ms. Foundation for Women named Watson its Feminist Celebrity of 2014, following an online poll. Watson also gave a speech about gender equality in January 2015, at the World Economic Forum's annual winter meeting.
Watson took the top spot on the AskMen "Top 99 Outstanding Women 2015" list on the strength of having "thrown her back" into women's rights issues. The day after she turned 25, Watson placed number 26 on the TIME 100 list of the world's most influential people, her first-ever appearance on the list. For its recap, former New York Times editor Jill Abramson noted Watson's "gutsy, smart take on feminism" and called the effort to get men involved "refreshing".
In January 2016, Watson started a feminist Goodreads book club: Our Shared Shelf. The goal of the club is to share feminist ideas and encourage discussion on the topic. One book is selected per month and is discussed in the last week of that month. The first book to be selected was My Life on the Road by Gloria Steinem, whom Watson would later interview on 24 February at the How to: Academy in London.
Watson was criticised in March 2017 for a photograph published by Vanity Fair in which her breasts are partly visible; some in the news media accused Watson of hypocrisy. She was bemused by the backlash, arguing that feminism "is not a stick with which to beat other women" but is instead about freedom, liberation and equality, commenting "I really don't see what my tits have to do with it."
In July 2019, Watson helped to launch a legal advice line for people who have suffered sexual harassment at work. Legal advice is provided by Rights of Women, a charity which works to help women through the law.