In recent years, impressive progress has been made towards our understanding of the basic mechanisms of immune- and cancer-cell biology. However, the complexity and dynamic nature of the interplay between the immune and cancer systems leaves many unanswered questions. In vitro cell-based assays are critical for probing these mechanisms and evaluating new potential treatments. Most recently, continuous live-cell analysis (CLCA) has emerged as a powerful addition to the laboratory line-up. CLCA is a non-invasive cell monitoring and measurement method based on time-lapse, phase-contrast microscopy and fluorescence imaging. In contrast to other methods, CLCA allows visualization and direct quantification of the full time course of the biology of interest rather than relying on arbitrary end-point measures.