Antimicrobial photodynamic therapy (aPDT) is emerging as a promising tool in veterinary medicine, not only for clinical applications but also for various nonclinical purposes. The therapy involves the use of photosensitizers activated by light to produce reactive oxygen species that can effectively kill a broad spectrum of microorganisms, including parasites, bacteria, fungi, and viruses. While aPDT is widely recognized for its use in treating infections, its nonclinical applications in veterinary medicine are gaining attention for their potential to enhance animal health and welfare. One significant nonclinical application of aPDT is in the decontamination of animal housing and equipment. In environments such as farms, kennels, and veterinary clinics, surfaces and tools can harbor pathogens that pose a risk of infection to animals. APDT offers a chemical-free, eco-friendly alternative to traditional disinfectants, reducing the risk of developing resistant microbial strains. Moreover, it can be applied to sensitive areas where the use of harsh chemicals is undesirable, providing a safe method for maintaining hygienic conditions. Another potential application is in the decontamination of animal feed and water. Contaminated feed and water can be sources of infection, particularly in large-scale farming operations. APDT can be used to reduce microbial load in feed and water supplies, contributing to better animal health and reducing the need for antibiotics, which aligns with global efforts to combat antimicrobial resistance. Thus, the nonclinical applications of aPDT in veterinary medicine hold great promise for improving animal health, enhancing biosecurity, and supporting sustainable farming practices. In this chapter, we present several innovative ways aPDT can be used in veterinary medicine.