For many years, functional molecules with multiple controllable and responsive properties have been at the center of major research efforts. Such molecules may combine, for example, the properties of polymers with response to heat, as in thermoplastic materials, or the properties of dyes with response to electricity, as in electrochromic materials. Responsive materials that display enhanced characteristics are gaining in versatility and leading to numerous new applications. Considerable progress has been made toward supramolecular assembly at interfaces. We will discuss the formation of films of metallosurfactants. Self-assembled monolayers, metallopolymers, and dendrimers will not be discussed.