This is the final report of a one-year, Laboratory-Directed Research and Development (LDRD) project at the Los Alamos National Laboratory (LANL). Current chemical sensors suffer from poor molecular specificity, sensitivity, and stability and seldom have the recovery properties needed for real-time monitoring applications. We have employed self-assembly techniques to covalently bond species- selective reagents directly to the surface of the transducer so that analyte/reagent chemistry occurs at the interface between the transducer and the media to be monitored. The use of self-assembling monolayer and -multilayer (SAM) techniques results in stable sensing elements with optimal specificity built in through the use of reagents that have been designed for molecular recognition. Moreover, self-assembly chemistry applied to oxide surfaces allows flexible means of transduction spanning optical, electrochemical, mass-loading, and conduction methods. The work conducted on this project focused on demonstration of the methodology and the application to selected organic vapors (aromatic compounds and halogenated hydrocarbons). We have been able to develop a series of surface acoustic wave (SAW) sensors that are specific for aromatic compounds and halogenated hydrocarbons based on self-assembled thin films of cyclodextrins and calixarenes. Monolayers of seven different cyclodextrins and clixarenes have been attached to SAW transducers and their response to several organic molecules in the vapor phase have been measured. This preliminary data confirms the efficacy of this approach for real- time monitoring of hydrocarbons.