Single crystals of [Ag(CN)(2)(-)]/NaCl and [Ag(CN)(2)(-)]/KCl show luminescence spectra that change drastically with temperature. The major luminescence band at 12 K is a UV emission at about 315 nm. Blue-green emissions in the 400-520 nm region appear upon an increase in temperature to 80 K. A further increase in temperature results in the disappearance of the blue-green emissions and the appearance of a high-energy UV emission at about 290 nm. The color changes are reversible and represent a new example of luminescence thermochromism. A kinetic model is proposed to show the radiative and nonradiative pathways at different temperatures. Highly resolved emission spectra are obtained upon a careful selection of the excitation wavelength. Individual peaks within the resolved emission bands are attributed to different geometrical isomers of a given *[Ag(CN)(2)(-)](n) cluster in the alkali halide lattices. The wide range of luminescence energy, the strong luminescence at ambient temperature, and the control of the profile of the emission spectra by controlling the excitation wavelength are desired properties for the design of new solid-state photonic devices based bn the Ag(I) luminescence.