Dynamics of the D2 line (2P3/2-2S1/2) excitation of atomic silver in liquid helium and cold helium gas will be discussed. The Ag atoms are produced by laser ablation of an Ag target followed by laser photodissociation of large Ag clusters. The excitation and laser induced fluorescence spectra are investigated. Also, LIF lifetimes are studied in He gas at various temperatures (4.3-25 K) and pressures (100-800 torr). In liquid helium, Ag relaxes to the ground state with formation of an AgHe2 exciplex. Deexcitation in the gaseous environment proceeds through formation of AgHe and AgHe2 exciplexes as well as population trapping and formation of a monoatomic liquid He layer on the Ag atom in the 2D5/2 state. The results are discussed using ab initio and semi-empirical models. Comparison between excitation dynamics of Ag and alkali atoms is drawn.