Despite being unelected and unappointed, first ladies of the United States have served as notable political assets and liabilities before, during, and after their time in the White House. This chapter uses a variety of examples to illustrate the positive and negative impacts of first ladies as they have exerted their influence domestically and internationally, sometimes in alignment with and other times in opposition to their husband’s public agenda. These pages delineate the ways these women have been strategically deployed as emissaries for their husbands and as advocates for party policies, initiatives, and candidates up and down the ballot, as well as how they have instigated and mitigated scandals. The amorphous and often contradictory criteria for being an effective first lady expose every presidential spouse to criticism that is not always reasonable given the nebulous nature of the position.