The CTAO and Synergy Programme Scientist will provide scientific leadership for ESO's participation in CTAO. In return for the effort to operate CTAO-S, ESO will have 10% of the open time on the northern and southern arrays. They will also be responsible for optimising the multi-wavelength/multi-messenger use across ESO's facilities and with other leading facilities. The Programme Scientist is responsible for developing and maintaining a strategic vision for multi-wavelength synergistic use of ESO facilities, including advising on and developing strategic partnerships with other astrophysical facilities both ground based, and in space. In particular, the Programme Scientist is responsible for maintaining a strategic scientific vision for CTAO and contributing to ESO's overall policy and long-term planning. They maintain professional contacts at the highest level outside the Organisation and, as postholder, will be assigned to the role for the full duration of the CTAO Programme. In addition, the Programme Scientist serves as the primary interface between CTAO and the broader ESO user community.

The Programme Scientist works closely with colleagues across the Directorate for Science (DSC) to ensure synergies with ESO's existing facilities and the optimal scientific use of ESO's share of observing time on CTAO in support of the Programme's goals. They will closely monitor the evolving scientific priorities of the community within the rapidly advancing landscape of astronomical facilities projected for the 2030s and beyond and foster broad community engagement in planning for the best multi-wavelength/messenger use of ESO's facilities, identify emerging scientific areas, and promote synergetic use of ESO's facilities through working groups, community days, and workshops, in close coordination with the Offices for Science. They also monitor and assess the scientific effectiveness of multi-wavelength use of ESO's facilities, developing strategies to maximise its impact and establishing best practices for both scientific capabilities and operations.

Strong coordination with CTAO is essential. In collaboration with the Communications Department, the Programme Scientist identifies and promotes key science drivers and results. They also work closely with the Observing Programmes Office, particularly for initiatives such as multi-telescope time allocation processes, and the promotion of large surveys and synergies with other ESO facilities, including ALMA.

Together with the Director for Science and other Programme Scientists, they contribute to shaping the Organisation's scientific strategy and play an active role in decisions affecting the capabilities of current and future facilities. The CTAO and Synergy Programme Scientist reports regularly to the ESO Advisory and Governing Bodies, principally on CTAO.