Purpose: This study aims to identify people's perceptions of what behaviourally differentiates effective managers from ineffective managers within a South Korean (SK) public sector organization, and the extent to which the findings are similar or different to those of an equivalent previous study in the SK private sector. Design/methodology/approach: Adopting the "pragmatic approach" and assuming a post-positivist ontology and constructivist-interpretivist epistemology, examples of "effective" and "ineffective" managerial behaviour were collected from managers and non-managerial employees in an SK central government Ministry using the critical incident technique. The collected critical incidents were coded, classified and reduced to a smaller number of behavioural categories. These were then compared against equivalent findings from a previous SK private sector replication study using open, axial and selective coding to identify generic behavioural criteria (GBCs). Findings: High degrees of convergence point towards the emergence of a "two-factor" SK behavioural taxonomy of perceived managerial and leadership effectiveness comprised of positive (n = 11) and negative (n = 4) GBCs of effective and ineffective managerial behaviour. Practical implications: The GBCs constituting the deduced SK behavioural taxonomy could be used by HRD practitioners to critically evaluate the efficacy of extant management and leadership development (MLD) programmes, or to inform/shape the creation of new MLD programmes. Additionally, they could be used by other HR professionals to critically evaluate the relevance and efficacy of the assessment criteria used for existing management selection, 360-degree feedback and formal performance appraisal systems. Originality/value: The emergence of an SK behavioural taxonomy through Type 3 (emic-as-emic) and Type 4 (emic-and-etic) indigenous research is a rare example of Eastern mid-range theory development.