The High Angular Resolution Monolithic Optical and Near-infrared Integral field spectrograph (HARMONI) is the first light instrument for the ELT, therefore, available as soon as the telescope enters into operations. The University of Oxford leads the international consortium
developing HARMONI, also comprised the Astronomy Technology (UKATC, Edimburgo), the University de Durham, the Centre de
Recherche Astrophysique (CRAL, Lyon), the Laboratoire d'Astrophysique de Marseille (LAM), the Instituto de Astrofísica de Canarias
(IAC), the Centro de Astrobiología (CAB/CSIC-INTA, Madrid), and the University of Michigan.

The kick-off of the construction of the HARMONI was in 2015, and the complex design of the instrument has been under development ever since. In September 2021, ESO submitted a Red Flag (RF) report to the project, indicating several technical and management concerns.
Since then, the HARMONI Consortium has performed a detailed review of the project needs, especially on the topics identified in the RF
report, which have resulted in some high-level requirements changes, with implications for most of the subsystems that make up the
instrument.

The general objective of this coordinated proposal is to support the Spanish participation in the development of HARMONI during the
Delta-D1 Phase, an interim phase between the implementation of the high-level changes in the instrument, and the estimated date when
ESO shall proceed to conclude the final design phase.