The Human Cancer Models Initiative is an international consortium that is generating novel, next-generation, tumor-derived culture models annotated with genomic and clinical data. Models and related data developed through the initiative are available as a community resource. NCI is contributing to the initiative by supporting four Cancer Model Development Centers. These centers are tasked with producing next-generation cancer models, such as organoids and conditionally reprogrammed cells, from clinical samples. The cancer models include tumor types that are rare, originate from patients from underrepresented populations, lack precision therapy, or lack cancer model tools. In 2018, a funding opportunity was offered to increase the racial and ethnic diversity of the samples used to develop new culture models.