In this study we have examined the effect of the SNARE protein syntaxin 1A on the glycine transporters GLYT1 and GLYT2. Our results demonstrate a functional and physical interaction between both glycine transporters and syntaxin 1A. Co-transfection of syntaxin 1A with GLYT1 or GLYT2 in COS cells resulted in approximately 40% inhibition in glycine transport. This inhibition was reversed by the syntaxin 1A-binding protein, Munc18. Furthermore, immunoprecipitation studies showed a physical interaction between syntaxin 1A and both transporters in COS cells and in rat brain tissue. Finally, we conclude that this physical interaction resulted in a partial removal of the glycine transporters from the plasma membrane as demonstrated by biotinylation studies.