The International Day of Women and Girls in Science, observed each year on 11 February, was established by the United Nations General Assembly in 2015 to recognize the critical role women and girls play in science, technology, engineering, and mathematics—and to address the persistent gender gaps that limit their full participation. Rooted in decades of global advocacy by women scientists, educators, and international organizations, the Day emerged from growing evidence that structural barriers, bias, and unequal access to education and leadership continued to exclude women from scientific careers, including ocean sciences. While women have always contributed to ocean knowledge—often invisibly as observers, data collectors, educators, and community knowledge holders—their work was historically underrecognized and underdocumented. The Day serves both as a celebration of achievements and a call to action, encouraging governments, institutions, and scientific communities to create inclusive, equitable environments where women and girls can thrive. In ocean sciences in particular, it highlights the importance of diverse perspectives in understanding and protecting the ocean, sustaining fisheries, and responding to climate change—affirming that the future of the ocean depends on the full and equal participation of women.