Far‐wing absorption profiles of the resonance lines have been studied for the metal aotms (Ca, Sr, Ba, Yb, and Hg) perturbed by rare‐gas atoms (He, Ne, Ar, Kr, and Xe) and some diatomic molecules by means of the classical double‐beam absorption and dispersion method and a laser‐pump and probe method.Reduced absorption coefficients (RAC’s) of the far‐wing continum bands are determined in absolute scale for thensnp1P1−ns21S0resonance lines of Ca, Sr, Ba and Yb perturbed by rare gases (the foreign‐gas broadening) and by the metal atoms (the self broadening) at temperatures of 950–1050 K. RAC’s for the Hg 6s6p3P1−6s21S0one broadened by N2, CO, H2, and D2are determined in absolute scale at temperatures of 410−480 K. The spectral ranges covered are about 20−2000 cm−1on either side of the respective line center.Using an inversion method based on the quasi static theory and employing the theoretical ground‐state potential curves calculated by the pseudo‐potential method, the RAC’s for the Ca‐He, Ca‐Ne, and Ca‐Ar systems are transformed to potential curves of theA1∏ andB1&Sgr; states. Blue‐wing oscillations observed for the rare‐gas broadened Ba and Yb resonance lines are analyzed in detail based on the uniform‐semiclassical approximation. These oscillations are due to the existence of a phase‐difference which is stationary against the change in the orbital angular momentum of the relative nuclear motion. Two main sources of such stationary phase‐differences are pointed out and relative importance of the two sources is discussed.A far‐wing excitation and probe method is applied to observe the partial line‐shapes of the Hg 6s6P3p1−6s21S0line broadened due to the fine‐structure transitions: Hg(3P1)N2, CO→Hg(3P0)+N2, CO, and the chemical reaction: Hg(3P1)+H2→HgH(X,v,j)+H. The partial line‐shapes broadened due to these specified processes are compared with the total line‐shapes obtained by the double‐beam absorption method. The red‐wing excitation is much more effective than the blue‐wing excitation in causing the fine‐structure transition and the chemical reaction.