This paper presents experiments that demonstrate the concept of energy sinks, which when attached to a vibrating structure can absorb most of its energy. Energy sinks consist of a set of undamped linear oscillators and, in principle, do not require presence of damping in the classical sense. The set of undamped oscillators that make up an energy sink collectively absorb the vibratory energy and retain it in their phase space. Earlier optimization studies by the authors have shown the feasibility of vibration absorption and energy retention by energy sinks if the set of oscillators have a particular frequency distribution. Experimental results presented in this paper support the concept of energy sinks. Different physical realizations of energy sinks demonstrate the significance of frequency distributions and the ability of energy sinks to reduce vibration amplitude of a primary structure to which they are attached. (c) 2005 Acoustical Society of America.