Gently heating a pyroelectric crystal in a deuterated atmosphere can generate fusion under desktop conditions. The electrostatic field of the crystal is used to generate and accelerate a deuteron beam (>100 keV and >4 nA), which, upon striking a deuterated target, produces a neutron flux over 400 times the background level. The presence of neutrons within the target is confirmed by pulse shape analysis and proton recoil spectroscopy. Several elements of the system may be modified, including the configuration of the crystal or crystals, the composition of the surrounding environment and the target, the use of multiple probe tips, and the composition of the probe tip.