The absorption, fluorescence emission, and photophysics of 4-(methoxyphenyl)-4’-[(dimethylamino)phenyl]-squaraine and its derivatives (USq1-USq14), a class of unsymmetrical donor-acceptor-donor (D-A-D) compounds, have been investigated. Similar to symmetrical and pseudo-unsymmetrical (with two different aniline rings) squaraines, USq1-USq14 also exhibit intense absorption bands in the visible region. Their absorption maxima (lambda(max)) range from 562 to 593 nm and are blue-shifted relative to those of symmetrical and pseudo-unsymmetrical squaraines. The blue-shift is attributed to the decrease in the D-A-D CT character, arising from the introduction of a less electron-donating anisole ring. As it turned out, the introduction of asymmetry through the anisole ring has a significant impact on the electronic spectra. The asymmetry in USq1-USq14 enhances vibronic coupling during electronic transition, producing vibrational fine structures in both absorption and fluorescence spectra. The vibronic coupling is particularly pronounced when the C-O group in the central four-membered ring is H-bonded, either intramolecularly or intermolecularly with solvent molecules. USql-USq14 are shown to form solvent complexes with solvent molecules. The multiple fluorescences observed for these compounds, although quite complex, are shown to be the sum of the vibronic bands of the unsymmetrical squaraine and its complex. At room temperature in solution, the phi(f) values for USq1-USq14 are a factor of greater than or equal to 30 lower than those of symmetrical and pseudo-unsymmetrical squaraines. Their lifetimes are less than or equal to 0.25 ns. There is a large temperature effect on both phi(f) and lifetime. At 77 K in a 2-methyltetrahydrofuran matrix, the phi(f) values approach greater than or equal to 0.5 and the fluorescence lifetimes increase to a constant value, similar to 2.4 ns. Hydroxy unsymmetrical squaraines are an exception; they exhibit biexponential decays (similar to 2.4 ns and a subnanosecond decay) at 77 K in 2-methyltetrahydrofuran. The observation may be attributable to a conformational effect. The large temperature effect on the photophysical processes indicates that there exists an efficient radiationless decay process for these compounds. Evidence is provided that rotation of the C-C bond between the anisole ring and the four-membered ring is responsible for the radiationless decay. The fast decay is attributable to the single-bond character of the rotating C-C bond in these compounds. Substituents, both in the aniline ring and the anisole ring, are shown to have effects on the electronic spectra. These substituent effects are discussed in terms of their effects on the D-A-D CT character of the squaraine chromophore.