  HARMONI is a visible and NIR integral field spectrograph, providing the
E-ELT's core spectroscopic capability at first light. HARMONI will work at the
diffraction limit of the E-ELT, thanks to a Classical and a Laser Tomographic
AO system. In this paper, we present the system choices that have been made for
these SCAO and LTAO modules. In particular, we describe the strategy developed
for the different Wave-Front Sensors: pyramid for SCAO, the LGSWFS concept, the
NGSWFS path, and the truth sensor capabilities. We present first potential
implementations. And we asses the first system performance.
