The Human Capital Operational Programme is a Romanian initiative to boost employment, enhance education and skills, combat poverty, and reinforce social services, focusing on youth, the Roma community, and rural residents. This paper investigates the overarching impact (direct, indirect, and induced) of the Human Capital Operational Programme investments during 2014–2020 on the formation of the Gross Domestic Product. In the context of a backdrop of intensive economic interventions, the study applies the Leontief input–output model, grounded in inter-sectoral relationships within the economy, to describe how outputs from one sector can become inputs in another. This approach accommodates the entire portfolio of financed projects, considering the funding amounts at both project and sector levels relevant to the applicant. Significant findings reveal that the direct contribution of the Human Capital Operational Programme to GDP was evaluated at 0.92% for the period 2014–2023, with the public administration and defence sector contributing approximately 44% of the total contribution. The indirect multiplier effect of the Human Capital Operational Programme investment on Gross Domestic Product growth was estimated at 0.32% for the same period. The total contribution of the Human Capital Operational Programme, summing direct, indirect, and induced effects, exceeds 2.04% for 2014–2023, with an induced effect evaluated at 0.81%, considering the action of household monetary flows. This paper’s contribution lies in providing a nuanced quantification of economic market interventions’ total impact, offering valuable insights for policymakers and stakeholders in economic development.