The prevailing poor prognosis of high-grade brain malignancy, such as isocitrate dehydrogenase 1 and 2 (IDH) wild-type gliomas and brain metastases (BrMs), is often attributed to the immunosuppressive mechanisms at play in the unique brain tumour microenvironment (TME), limiting the effects of treatments. Although tumour-associated neutrophils (TANs) are known to be among brain-infiltrating immune cells, their role in brain malignancies was incompletely defined. Maas et al. now comprehensively analyse TANs in patients with brain malignancies.