Better understanding of the tumour microenvironment, and its influence on response to therapy, is key to developing the right strategies to target specific tumour antigens and kill the cancer cells. By studying the different cell types – T cell, myeloid cells, fibroblasts, NK cells, B cells, etc. -- and their roles in tumor initiation, progression, and resistance, companies can better predict response to therapy, and thereby design better immunotherapies to target solid and hematologic cancers.