Cancer Heterogeneity and Plasticity is an international, peer-reviewed, Open Access (OA) journal dedicated to showcasing outstanding original research articles, reviews, and perspectives spanning the dynamic realm of cancer cell heterogeneity and adaptability and the complexities within their microenvironments. Its scope encompasses a wide spectrum of topics, including but not limited to the elucidation of evolutionary relationship of cancer cell subpopulations (i.e., heterogeneity), molecular mechanisms driving cancer cell plasticity (e.g., epithelial-mesenchymal transition or EMT), epigenetic underpinnings of cancer cell reprogramming (e.g., treatment-induced neuroendocrine (NE) transdifferentiation), and the influence of the tumor microenvironment (TME) on cancer cell dynamics. It extends to embrace studies exploring the impact of the microenvironment and systemic host factors (e.g., hormones, growth factors, inflammatory cytokines, and nerves) on cancer progression, therapeutic resistance, cancer cell dissemination and dormancy, metastasis, and the development of innovative targeted and combinatorial therapies.