According to the contingency theory, there is no single best way to structure an organization. Instead, the suitability of organizational structures and characteristics depends on internal and external contingencies (Donaldson 2001). Only after considering the costs and benefits of different possibilities, while also allowing for internal and external contingencies, can the most efficient alternative be chosen. In this way, organizational structure and characteristics are shaped by situational factors (e.g., Child 1975; Schreyögg 1980).
We apply this logic to researching the reasons for CHRO presence in TMTs. In line with previous research that applies the contingency perspective (Hambrick and Cannella 2004; Menz and Scheef 2014; Nath and Mahajan 2008; Zorn 2004), we base our analysis on the assumption that CHRO presence is more useful, and therefore more likely, when HR issues cause complexity and uncertainty at the apex of a firm. By analyzing prior empirical and theoretical publications, especially from within research streams on TMTs (Finkelstein et al. 2009; Menz2012) and SHRM (Caldwell 2003; Welbourne and Andrews 1996), and condensing the indicative evidence extracted from our qualitative research, we focus on five regularly-occurring factors that increase HR complexity at the top of an organization, and thus drive the appointment of a CHRO. These are the representation of unions, the knowledge-intensity of a firm, major strategic or organizational changes indicated by changes in the number of employees, and employment of a new or outsider CEO.