Uveal melanoma is the most common primary tumour to develop within the eye in dogs, arising from melanocytes in the iris, ciliary body, or choroid — collectively known as the uvea. The biology of uveal melanoma in dogs is notably different from melanoma at other sites: approximately 80% are benign melanocytomas with a very low metastatic rate (about 3%). These benign tumours are typically slow-growing and may be observed for years without intervention, though they can eventually cause secondary problems such as glaucoma (increased eye pressure) or uveitis (inflammation within the eye). When secondary complications arise or the tumour grows rapidly, removal of the eye (enucleation) is typically curative. The key clinical challenge is distinguishing benign from the less common malignant form, which has a higher risk of distant spread.