In the field of strategic management, scholars have constantly acknowledged the importance of the adoption of management practices with respect to firm outcomes. Still, evidence indicates that firms do not implement management practices ubiquitously. The factors that lead to such variations have only been explored to a limited extent. As a result, there is no unifying theory in this respect and empirical evidence is limited. In this thesis, I suggest that variations in management practices are likely to be associated with different firm contexts, different leader cognitions and behaviours. On the basis of these criteria, three papers have been developed. Due to the vast amount of management practices identified in research, the analysis in all three papers focuses specifically on the implementation of Human Resource Management (HRM) practices. In Paper 1 (Chapter 2), the theoretical and empirical issues associated with the relationship among contextual factors, management practices, and performance are discussed. Due to these issues, an inductive approach based on fuzzy-set analysis is adopted. Papers 2 and 3 (Chapters 3 and 4) aim to shed light on the connections between specific leader cognitions, behaviours, and management practices. Due to the general-level theoretical rationale and limited empirical evidence, Paper 2 has been developed as a review paper, and involves the development and application of a conceptual framework. The paper concludes with a research agenda proposing the adoption of fuzzy-set analysis to develop theoretical insights on the relationship between leadership and management practices. Based on the conceptual framework and research agenda proposed Paper 2, an empirical is undertaken in Paper 3. The analysis provides insights on the connections between specific leader cognitions, specific leader behaviours, and specific management practices. Findings from these papers shed light on variations in management practices across firms. All three papers lead to important theoretical implications with respect to the configurational perspective of HRM, aside from other specific theoretical implications associated with each individual paper. Moreover, practical implications for firm leaders and policymakers on the adoption of management practices are outlined.