  We show that a muon collider is ideally suited for the study of heavy H/A
scalars, cousins of the Higgs boson found in two-Higgs doublet models and
required in supersymmetric models. The key aspects of H/A are: (1) they are
narrow, yet have a width-to-mass ratio far larger than the expected muon
collider beam-energy resolution, and (2) the larger muon Yukawa allows
efficient s-channel production. We study in detail a representative Natural
Supersymmetry model which has a 1.5 Tev H/A with $m_H$- $m_A$ = 10 Gev. The
large event rates at resonant peak allow the determination of the individual H
and A resonance parameters (including CP) and the decays into electroweakinos
provides a wealth of information unavailable to any other present or planned
collider.
