Take-home Message:Does ligand potency dictate the signalling that is initiated to activate a CD8+ T cells? In this paper, Richard et al. shows, using a myriad of cutting-edge techniques, that ligand potency plays a role for the kinetics of activation (more potency = less time to signalling and more uniform activation of a population), but not on the end point, which is the ability to become cytolitic. Importance: This paper adds to the debate about the strength of ligand and endpoint signalling in CD8 T cells, but it is also an excellent resource paper that shows what can be done with recent technologies.