The author offers a theoretical examination of the concept of a human resources (HR) architecture and its two main dimensions: vertical alignment and horizontal consistency. Regarding vertical alignment, the author theorizes that, on the whole, organizations that are of the same type and that operate in the same kind of environment have similar HR architectures, because they share a common foundation of human resource management (HRM) practices and objectives. In other words, when organizations are subjected to the same environmental pressures, certain objectives become imperative. Using a detailed example from the field of public health, the author presents the causal chain that links the strategic summit to organizational outcomes through the implementation of HR objectives, practices and outcomes. However, just because two organizations have the same fundamental HRM objectives, imposed by the forces of the outside environment, this does not necessarily mean that these organizations will design and implement these objectives in the same way or to the same extent. The design, implementation and maintenance of HRM objectives all depend on three criteria: the organization's capacity to implement them (e.g., financial, technical and other resources), the capabilities of the main people involved (e.g., HRM professionals and consultants, management leadership, managers' and supervisors' skill sets, etc.), and the general support that the organization provides for these objectives (organizational culture, work climate, HR philosophy and values, management commitment, and stakeholders' participation). These three criteria should have a decisive impact on (a) the quality of the content of the organization's HRM programs, (b) the speed with which these programs are implemented, (c) their life cycle, (d) their cost, (e) their practicability, (f) their adaptation to internal contingencies, and g) their acceptability to managers and employees. Thus, the success of HRM objectives and practices is determined not only by how much they are made necessary by environmental forces and how closely they are linked with the organization's strategic objectives, but also by a set of conditions conducive to their achievement and by the ability of HR strategists to understand these contingencies and to influence organizational and HR strategic decisions. In order to facilitate valid choices for HR objectives, the "key success factors" approach is recommended as a strategic planning method. Identifying key success factors helps clarify the causal relationships between the organization's objectives and the HRM objectives and practices that should be implemented so as to exert a positive influence on the performance of the organization's members. Because key success factors often typify a class of industries, organizations that are of the same type and that are influenced by the same environment might be expected to have similar key success factors. The author thus next examines how the vertical alignment process produces unique features in the HR architectures of different organizations of the same type. He hypothesizes that, although organizations of the same type tend to start with a common foundation of HRM practices, the adjustment of these practices to the organization's internal contingencies causes their content and the processes they involve to become differentiated. What makes an organization's HR architecture unique is the complex adjustment of its HR practices to the internal contingencies of its environment. Therefore, even though they may be referred to by the same names, HRM practices differ significantly from one organization to the next, and this accounts for differences in their potential impacts. The author then presents a model of internal contingencies, which he classifies into three main groups: (a) organizational (e.g., corporate culture, corporate structure), (b) operational (e.g., product life cycles, production technologies) and (c) human (work force characteristics, predominant management style). This model comprises at least 120 cells, each of which represents a unique combination of human, organizational, and operational contingencies. This model represents a set of hypotheses to be tested. Certainly not all of these contingencies have the same degree of influence. The influence of some of them (such as culture) is more generalized, whereas the impact of others (such as production technologies) is more circumscribed. Lastly, it may be that at certain times, certain contingencies (such as relations with unions) predominate while others are neglected, so that HRM practices implemented under the effect of one particular contingency may impair the effectiveness of other existing or future HRM activities. HRM practices that are harmonized on the basis of internal contingencies may act either as facilitators of, or obstacles to, the achievement of strategic objectives. Thus, HRM practices that reinforce an "obstacle contingency" hurt the organization, because they support a contingency that impedes the achievement of priority objectives. It is therefore essential to determine which contingencies are acting as facilitators and which ones are acting as obstacles, so that the former can be reinforced, while the latter can be modified in the desired direction. However, alignment on internal contingencies does not guarantee that practices will be complementary to one another. For that, it is necessary to directly verify the horizontal consistency of HRM practices. The author proposes an operational definition of horizontal consistency and suggests some direct steps that can be taken to ensure it. The theoretical discussion demonstrates not only the unique nature of HRM in terms of the consistency of practices, but also the complexity of the linkages when vertical alignment is taken into consideration simultaneously. Thus, even if the vertical causal links are "apparently" well developed, many problems of inconsistency among HRM practices can arise. The author illustrates these problems with practical examples. In conclusion, a model that combines the two key dimensions of HR architecture offers opportunities to examine their interactive effects on organizational performance. The author offers many examples to clarify the meanings of the concepts discussed, as well as hypotheses to suggest avenues for further research. The author ends by stressing the importance of better understanding the influence of key success factors on the choice of HRM objectives and practices, and the need to better identify the internal contingencies that affect the content of these practices and their consistency with one another.
