|Interactions between microorganisms are prevalent in nature, and often occur in biofilms that exist as dynamic micro-environments. To capture metabolic exchange between microorganisms derived from dental biofilms, matrix laser desorption ionization (MALDI) imaging mass spectrometry (IMS) was used, and demonstrated that molecules produced by Lactobacillus inhibit Streptococci. MALDI-TOF and tandem MS were used for structural elucidation of molecules that may be responsible for inhibition. Ultimately, these studies will lead to an understanding of molecular interactions between oral organisms in the formation of dental biofilms. A network map of molecules will be created, and can be directed towards an approach that models microbial community dynamics.