Co-directors Ella Magers and Gretchen Primack organized the effort following the successful closure of Wisconsin’s Ridglan Farms, which resulted in the rescue of over 2,000 beagles. The organizers view the grueling physical nature of the march as a necessary contrast to the conditions experienced by animals held in laboratory pipelines. They are joined by a coalition of national groups, including the Physicians Committee for Responsible Medicine and the Center for a Humane Economy, to advocate for the adoption of non-animal research methods.

Marshall BioResources remains one of the world's largest suppliers of research animals. The march serves as a coordinated international effort, with the group Save the Dogs organizing a parallel demonstration in London to coincide with the final rally in New York on September 26. Beyond the immediate focus on Marshall BioResources, the campaign seeks to overhaul federal research policies, arguing that current animal models are scientifically inferior to modern, human-relevant alternatives.