The article investigates the central role of water in European baroque gardens by using selected examples from Italy, France, Germany, and Spain. It focuses on the significance of water for the organization of space, the variety of its artful mise en scène in different fountain types, its multi-faceted symbolism, and on its performative possibilities concerning a physical as well as psychical involvement of the garden visitor. It is mainly the ambivalent materiality of water—its mutability, movement, transparency, and reflective quality—that define the Baroque’s affinity to this ephemeral and entirely atectonic element that activates different senses simultaneously and is particularly suited for a synesthetic experience of the garden. Yet, water displays also assumed an important role for sociability, as they could determine different moods in various parts of the garden, create amusement and intimacy between the visitors, and raise their awareness of hierarchies and power relationships by the demonstration of technical mastery.