Here we discuss the preparation and characterization of photopolymerizable, self-assembled monolayers (SAMs) that consist of acid-, hydroxyl-, and methyl-terminated n-alkanethiols containing a diacetylene group (HS(CH2)10C⋮CC⋮C(CH2)10X; X = COOH, CH2OH, and CH3, respectively). The acid and hydroxyl surfaces are readily amenable to further synthetic elaboration, while the methyl-terminated SAM results in a clean, low-energy surface. As demonstrated by Fourier transform infrared external reflectance spectroscopy (FTIR-ERS), surface-enhanced Raman spectroscopy (SERS), ellipsometry, UV−vis spectroscopy, and electrochemical methods, all three materials self assemble onto Au surfaces to form ordered monolayers that can be photopolymerized with UV light.