Known as the "clown" of the spaniel family, the Irish Water Spaniel is the largest and one of the oldest breeds of spaniels. Although the current breed stock are Irish, the ultimate origin of the breed is unknown. It is possible that more than one ancient breed of spaniel has gone into its makeup. Irish Water Spaniels share a common lineage with the Poodle, Portuguese Water Dog, and Barbet, but whether they are antecedents, decendents, or mixtures of these other breeds is a matter of some speculation. What is clear is that the breed has ancient roots. The modern breed as we know it was developed in Ireland in the 1830s.

The Irish Water Spaniel resembles a stocky Poodle. The coat consists of dense curls, sheds very little, and is a solid liver color. The dogs are strongly built, and a bit taller and more squared than other spaniels. There is a curly topknot upon the head and the face is smooth. The most distinguishing characteristic of these dogs is their long "rat-like" tails, which are a striking contrast to their otherwise curly coats. Dogs range in height from 22 to 24 inches (56-61 cm), and weigh 55 to 65 pounds (25-30 kg).

This is an active breed that is usually found in a real working retriever environment. They are intelligent, quick to learn, alert, and inquisitive. They sometimes display humorous antics while working, earning them their "clownish" reputation. With proper socialization they can be gentle dogs with family and children, but are often shy around strangers. Irish Water Spaniels require lots of exercise and need an experienced trainer, and therefore are probably not the best choice for a casual dog owner.