The influence of internal HRM activity fit on the dynamics within the “black box”

• We describe how different types of internal fit influence important work outcomes.
• We consider the importance of mediating phenomena.
• We also explore how HRM activities interrelate to create synergistic effects.

Research has often called for studies to explain the complex causal chain known as the “black box” between human resource management (HRM) activities and individual-, unit-, and firm-level outcomes. To explore the dynamics within the “black box,” this article describes the influence of HRM activities (e.g., HRM policies, practices, and processes) on individual-, unit-, and firm-level outcomes, taking into consideration important mediating phenomena within the “black box,” such as human capital resources, motivation, and opportunities. Yet, we suggest that this basic understanding is insufficient to understand the dynamics within the “black box.” To fully comprehend how HRM activities affect outcomes across levels of analysis through the “black box,” one must consider how HRM activities interrelate to create positive (negative) synergistic effects. This research contributes to the literature of strategic HRM research by describing how and why aligned and interrelated HRM activities can create synergistic effects that may influence individual-, unit-, and firm-level outcomes through the “black box.” The described theoretical framework leads to the development of propositions to guide future research.