Cancer researchers published new immune-cell mapping work aimed at separating the roles of tumor-infiltrating cells that attack versus those that support malignancy. The study focuses on how immune populations can assume dualistic functions inside the tumor microenvironment. By charting immune-cell states and activities, the work seeks to address a long-standing obstacle in immuno-oncology: therapeutic failures driven by an inability to distinguish when the immune system is acting against tumors versus being co-opted. The findings set up testable hypotheses for precision immunotherapies that modulate specific immune-cell programs rather than broadly altering immune activity.