Nicholas Chiorazzi, MD, Feinstein Institute for Medical Research, Manhasset, NY, discusses important findings relating to the interaction between chronic lymphocytic leukemia (CLL) cells and other cells in the tumour microenvironment. Firstly, toll-like 9 receptor signalling was linked to CLL cell trafficking, findings which may be incorporated to help predict outcomes with ibrutinib therapy. Secondly, B-cell antigen receptor signalling was reported to be both necessary and sufficient for the development of Richter’s syndrome in a TCL1 transgenic animal model. Lastly, in CLL patients, fibroblastic reticular cells were found to have abnormal functions, impairing the immune response to CLL cells. Overall, these findings identify the toll-like 9 receptor, B-cell antigen receptors and fibroblastic reticular cells as molecular and cellular targets for further study in CLL. This interview was conducted during the 2021 virtual international workshop on CLL (iwCLL).