Urinary tract infections (UTI) are the second most common infection, impacting nearly 50% of all women. Indeed, otherwise healthy, premenopausal women have a significantly greater incidence of urinary tract infection (UTI) than men, yet, conversely, male UTI is more persistent with greater associated morbidity. Additionally, both sexes are at significant risk of reinfection, suggesting that adaptive immune responses to this infection are insufficient. Our group is interested in identifying the mechanisms that govern sex bias and development of immunity in UTI. Our recent work demonstrates that resident macrophages impair the adaptive response and that IL-17 is a critical player in resolution of infection. Currently, we are dissecting the initial events leading to a specific effector cell response and how this response can be immunomodulated for improved therapeutics that obviate the need for antibiotics to treat multidrug resistant uropathogens.