The effect of coinclusion of alcohol (ROH) on the stoichiometry, stability, spectral, as well as photophysical properties of beta-cyclodextrin (beta-CD) complexes of 4H-1-benzopyran-4-thione (BPT) was studied. Although the binary complex was of 1:1 stoichiometry, the formation of ternary complexes of 1:2:2 BPT:ROH:beta-CD stoichiometry was observed. The formation of the ternary complexes is revealed by a dramatic enhancement of fluorescence from the second excited singlet state and phosphorescence occurring from the two lowest thermally equilibrated triplet states. The increase in intensities of these emissions is discussed in terms of shielding the emissive molecule from bulk water molecules and expulsion (perhaps still partial) of water molecules coincluded with the BPT molecule in the binary complex. Even the coinclusion with a molecule that acts in solution as a very efficient quencher of BPT phosphorescence led to a very strong phosphorescence enhancement, which indicates that there is a spatial separation of reactive centers of the two coincluded molecules. The possible reasons for the changes in the shape in the phosphorescence spectrum and the appearance of vibrational structure in the S-2 band in the absorption spectrum are also discussed. The stability constants of the ternary complexes determined from absorption, fluorescence, and phosphorescence measurements depended strongly on the molecular size and structure of a coincluded alcohol.