We focus on inelastic neutron scattering in $URu_2Si_2$ and argue that observed gap in the fermion spectrum naturally leads to the spin feature observed at energies $omega_{res} = 4-6 meV$ at momenta at $bQ^* = (1pm 0.4, 0,0)$. We discuss how spin features seen in $URu_2Si_2$ can indeed be thought of in terms of {em spin resonance} that develops in HO state and is {em not related} to superconducting transition at 1.5K. In our analysis we assume that the HO gap is due to a particle-hole condensate that connects nested parts of the Fermi surface with nesting vector $bf{Q}^* $. Within this approach we can predicted the behavior of the spin susceptibility at $bQ^*$ and find it to be is strikingly similar to the phenomenology of resonance peaks in high-T$_c$ and heavy fermion superconductors. The energy of the resonance peak scales with $T_{HO}$ $omega_{res} simeq 4 k_BT_{HO}$. We discuss observable consequences spin resonance will have on neutron scattering and local density of states.
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