History is replete with examples of military forces succumbing to vector-borne diseases and being rendered ineffectual. In the austere environment of Iraq during Operation Iraqi Freedom, U. S. Navy Entomologists assigned to I Marine Expeditionary Force, Camp Pendleton, California took the fight to the field to prevent endemic vector-borne diseases from depleting the combat strength of the Marine, Navy, Army and Air Force Units assigned to the Al Anbar Province. Utilizing various techniques, including training troops on personal protection methods, such as treating uniforms with repellents and advocating the use of topical repellents, to the application of pesticides for the control of vectors, Navy Entomologists made sure that the combat strength of the operating units was not compromised by vector-borne disease. Major pests of concern included: sand flies, the vector of leishmaniasis; mosquitoes, the vector of focally endemic malaria; filth flies, vectors of a myriad of enteric diseases; feral dogs, which had the potential to be rabid; and rodents, which not only could vector disease but cause destruction of vital supplies. Additionally, even when pest arthropods and other animals were not a disease vector threat, actions by Navy Entomologists greatly improved the overall comfort of the troops by giving them relief from being bitten and the nuisance of pests.