This project proposes an integrated suite of microscopy and data analysis advances that would enable quantitative, mechanistic analysis of immune-microenvironment dynamics in poor prognosis solid tumors. While immunotherapies are showing remarkable clinical responses in some advanced cancers, to date, their impact on many solid tumors has been modest. This is due, in part, to solid tumor microenvironments limiting the effectiveness of natural immune responses and immunotherapies. Yet, our understanding of the physical and molecular mechanisms governing T cell infiltration, distribution, and function in native tumor microenvironments remains extremely limited. As such, defining key T cell behaviors as a function of complex tumor microenvironments will identify design criteria that can be used to develop novel cell engineering strategies that optimize T cell-centric therapies for solid tumors. To this end the research theme of the U54 Center for Multiparametric Imaging of Tumor Immune Microenvironments (C-MITIE) is to define physical and molecular barriers to effective anti-tumor immunity and immunotherapies through advancement and development of state-of-the-art live cell and tissue optical imaging platforms and quantitative analyses. To achieve our goals, our framework brings together advanced optical imaging platforms, nano- and micro- fabrication, genome engineering, cancer immunology, and biophysical modeling. Thus, from this integrated effort we seek to define mechanisms of immune suppression that guide the development of next-generation cell-based immunotherapies.