Everyone agrees about how long-term potentiation (LTP) is induced-NMDA receptor activation-but much remains to be learned about how the increase in the strength of a synaptic connection between two neurons is expressed. In this issue of Neuron, Kim et al. report a new form of NMDAR-dependent plasticity that may contribute to LTP: internalization of postsynaptic Kv4.2 potassium channels that mediate transient IA-type outward current in dendrites.