The 4d(10)-->4d(9)5s(1) transitions of the Ag+ ion in single crystals of NaF were investigated by one- and two-photon spectroscopy and luminescence experiments. The one-photon absorption spectrum extends from 238 to below 180 nm. At low temperature, several bands show resolved fine structure, but compared to NaF:Cu+, there is much less, and the lines are broader. The Jahn-Teller effect is much larger in Ag+ than in Cu+ and has been identified in three of the excited states. Trapping in Jahn-Teller minima is shown to change the emission kinetics radically compared to Cu+. The off-center force from the d(9)p states has much less effect on Ag+ than on Cu+. All of the evidence shows that Ag+ is more strongly coupled to the lattice than is Cu+.