Titanium dioxide is known to be a non-selective photocatalyst for the treatment of polluted air and water. An approach for obtaining selectivity, thus facilitating its use for the mineralization of hazardous, non-biodegradable contaminants is presented hereby. This approach is based on the construction of molecular recognition sites (MRS) anchored on inert domains in the vicinity of photoactive sites. These MRS are designed to physisorb target molecules and to "shuttle" them to the photocatalytic sites. Care is taken to prevent the photocatalytic degradation of the MRS, since (as we have found before) the photoinduced oxidizing species are, in principle, able to attack molecules anchored in the vicinity of titanium dioxide domains. Here we present several examples of selective photocatalysis by means of molecular recognition, based on the trapping of target molecules on thiolated cyclodextrins sites, followed by surface diffusion and photodegradation of the contaminants. The prospects and limitations of this approach will be discussed.