A promising approach for cancer immunophenotyping, in the context of clinical trials, is the usage of in situ multiplexed immuno- fluorescence (mIF) assays. We demonstrate Discovery’s highly standardized approach to novel mIF assay implementation (Fig. 1), focusing on the key steps in the wet lab procedure. Detailed phenotyping of spatial distribution patterns within the tumor microenvironment e.g., localization of lymphocytes, myeloid cells, fibroblasts and blood/lymphatic vessels, is an increasingly important tool for the identification of novel prognostic and predictive biomarkers for personalized cancer therapy.