Chancroid is a sexually transmitted genital ulcerative infection commonly found in developing countries. The infection is caused by Haemophilus ducreyi, a gram-negative bacterium with outer membrane proteins that allow the pathogen to move through breaks in the epithelial lining of the genitals and adhere to the dermis. One of the major outer membrane proteins responsible for adhesion is Ducreyi serum resistance A (DsrA), which binds to fibronectin in the extracellular matrix. The current treatments for chancroid infections are antibiotics. However, due to the high cost and minimal availability, probiotic therapy is being considered as an alternative treatment. Three interference assays: competition, displacement, and blockage by exclusion were utilized to see how adherence was affected by Lactobacillus. I predicted that the dsrA mutant would not bind to the lysine or fibronectin coated plates as well as the wild type. My hypothesis was not supported. Both the interference and noninterference binding assays showed no significant difference between mutant and parent binding. The ANOVA showed a significant difference among the probiotic assays. The blockage by exclusion and competition assays were significantly different from each other. I predicted that the blockage by exclusion assay would greatly reduce adherence and my hypothesis was supported. I suspected that a mix of the two Lactobacillus strains would inhibit adhesion more than the individual strains. The ANOVA showed no significant difference among these treatments types. In conclusion, no significant difference was found among the pathogens, or among the Lactobacillus treatment types. However, timing of probiotic interference does significantly affect pathogen adherence.