While a range of bacterial agents are a recognized cause of equine abortion, Chlamydia psittaci has emerged as a cause of reproductive loss as well as zoonotic disease of veterinarians and stud workers. This investment aims to reduce pregnancy losses in Australia's thoroughbred industry through an improved understanding of the epidemiology of this disease, focussing on two key aspects of this disease, the infected mare and the potential avian reservoirs of C. psittaci infection.