Moral integrity is a key aspect of business, raising trust and reliability among stakeholders. Within servant leadership, moral integrity is principal, aligning with the principles of prioritising the well-being of team members, customers, and stakeholders in general and cultivating ethical conduct. This study investigates the relationship of moral integrity, altruism, open-mindedness, and rational knowledge in the context of servant leadership, aiming to elucidate their roles in shaping ethical decision-making processes and leadership effectiveness in organisational settings. We address the gap in the practical application of servant leadership principles by posing research questions that explore into rational knowledge, the influence of altruism and open-mindedness on moral decision-making processes. Drawing from a comprehensive literature review, we establish the theoretical background for each construct. Using a quantitative survey, we employ validated scales to measure each construct and analyse the data using Partial Least Squares Structural Equation Modeling (PLS-SEM). The results underscore the significance of moral integrity as a driver of organisational success and ethical behaviour. Rational knowledge is a mechanism for open-mindedness and altruism, promoting moral integrity within organisations. This study contributes valuable insights for organisations seeking to cultivate ethical cultures, promote servant leadership principles, and survive in the long term.