Exciting new work identifies phospholipase D2 (PLD2) as an unexpected player upstream of Ras activation in epidermal growth factor (EGF)- and T-cell receptor-regulated signalling pathways. Phosphatidic acid (PA) generated on the plasma membrane by activated PLD2 directly recruits the guanine nucleotide-exchange factor Sos, or after conversion to diacylglycerol (DAG), recruits RasGRP1. These results demand a rewiring of some well-established circuit diagrams.