Spatial technologies and artificial intelligence are rapidly transforming tissue-based research, but generating high-dimensional images is only the first step. Extracting reproducible biological insight requires computational methods capable of identifying cells, defining phenotypes, mapping spatial relationships, recognizing multicellular neighborhoods, and integrating tissue architecture with molecular and clinical information. This Topical Collection will highlight practical and reproducible computational approaches for transforming histology, multiplex imaging, and spatial omics data into quantitative representations of tissue biology. Emphasis will be placed on methods that characterize the tumor immune microenvironment, including cell segmentation and phenotyping, spatial statistics, neighborhood analysis, multimodal image registration, deep learning, computational pathology, and integration of spatial proteomic and transcriptomic data.