Belén Sisa is a political activist and student based in Arizona. She is originally from Buenos Aires and is a DREAMer. In February 2019, Sisa was hired by Bernie Sanders to be his national press secretary.

Sisa came to America when her parents overstayed their visa when she was 6.

They settled in Gilbert, Arizona. She qualifies as a DREAMer, an Obama-era policy that protects the children of undocumented immigrants from deportation. After graduating from Florence High School, she attended Chandler-Gilbert Community College before transferring to Arizona State University. She is currently a junior and studies political science.

On March 26, 2017, Sisa posted on her Facebook profile of her paying taxes to the state of Arizona. Her post is trying to bring awareness to undocumented workers who pay taxes but do not receive benefits because of their legal status. Her story has had significant media coverage in the following days after her post.

Sisa was one of two undocumented DREAMers who acted as pagers for the 2016 Democratic National Convention. She initially campaigned for Bernie Sanders where she

worked in Latino Outreach but ended up voting for Hillary Clinton in the general election. Sisa is currently the Assistant Organizer and Communications for the Progressive Democrats of America.