Purpose: The study examined the relationship between data-driven leadership and decision-making effectiveness in South African public sector organizations, with a focus on the mediating role of organizational data culture. It aimed to understand how leadership behavior and a data-oriented culture influence the quality and timeliness of decisions in government institutions.

Methodology/Design: A quantitative research approach was adopted, employing Structural Equation Modeling (SEM) to test the hypothesized relationships. Data were collected from 420 public sector employees across multiple departments in South Africa. Reliability and validity were assessed through Cronbach’s alpha and confirmatory factor analysis, while the structural model tested the direct and indirect effects among constructs.

Findings: The results indicate that data-driven leadership has a significant positive effect on decision-making effectiveness (β = 0.59, p = 0.001). Organizational data culture also positively influences decision-making effectiveness (β = 0.46, p = 0.001). Additionally, data-driven leadership significantly mediates the relationship between organizational data culture and decision-making effectiveness (β = 0.31, p = 0.001).

Implications: The findings highlight the critical role of leadership and data culture in improving decision outcomes in the public sector. Policymakers and administrators are encouraged to invest in data literacy, analytics skills, and the cultivation of a strong data-oriented organizational culture to enhance governance, accountability, and service delivery.