  This project exploits charged particles confined as a storage ring beam
(proton, deuteron, possibly $^3$He) to search for an intrinsic electric dipole
moment (EDM, $\vec d$) aligned along the particle spin axis. Statistical
sensitivities can approach $10^{-29}$~e$\cdot$cm. The challenge will be to
reduce systematic errors to similar levels. The ring will be adjusted to
preserve the spin polarization, initially parallel to the particle velocity,
for times in excess of 15 minutes. Large radial electric fields, acting through
the EDM, will rotate the polarization ($\vec d \times\vec E$). The slow rise in
the vertical polarization component, detected through scattering from a target,
signals the EDM. The project strategy is outlined. It foresees a step-wise
plan, starting with ongoing COSY activities that demonstrate technical
feasibility. Achievements to date include reduced polarization measurement
errors, long horizontal-plane polarization lifetimes, and control of the
polarization direction through feedback from the scattering measurements. The
project continues with a proof-of-capability measurement (precursor experiment;
first direct deuteron EDM measurement), an intermediate prototype ring
(proof-of-principle; demonstrator for key technologies), and finally the high
precision electric-field storage ring.
