A method and apparatus for accumulation of hyperpolarized 129X e is disclosed. The method and apparatus of the invention enable the continuous or episodic accumulation of flowing hyperpolarized 129Xe in frozen form. The method also permits the accumulation of hyperpolarized 129Xe. The invention further includes 129Xe accumulation means (17) which is integrated with 129Xe hyperpolarization means in a continuous or pulsed flow arrangement. The method and apparatus enable large scale production, storage, and usage of hyperpolarized 129Xe for numerous purposes, including imaging of human and animal subjects through magnetic resonance imaging (MRI) techniques.