Kathleen Tierney and Michel Bruneau (Bruneau et al., 2003) conducted extensive work on the subject of resilience and it is a part of the literature reviewed. A signature aspect of their research on resilience is encapsulated in the 4 Rs concept of resilience. Within the research (Tierney, 1997), determined that four predominant concepts exist, which are:
- Robustness is the ability of systems, system elements, and other units of analysis to withstand disaster forces without significant degradation or loss of performance.
- Redundancy is the extent to which systems, system elements, or other units are substitutable, that is, capable of satisfying functional requirements, if significant degradation or loss of functionality occur.
- Resourcefulness is the ability to diagnose and prioritize problems and to initiate solutions by identifying and mobilizing material, monetary, informational, technological, and human resources.
- Rapidity is the capacity to restore functionality in a timely way, containing losses and avoiding disruptions.
Within previous literature, Tierney (1997) articulates the organizational aspects of: disaster response. Tierney explains, “The overarching principle guiding the discussion that follows is that organizations responding to disasters face the dual challenge of coordinating and structuring their activities according to pre-existing plans and agreements, while also allowing for improvisation” (p. 23). Tierney adds,
- While planning and training do contribute in major ways to the effectiveness of disaster response activities, because disasters always involve challenges not addressed in prior plans, effectiveness also rests on the capacity to be resilient and flexible in the face of those unexpected challenges. (p. 24)
- To be effective, organizational responses to disasters, Harrald (2006) states, must ensure both discipline (structure, doctrine, and process) and agility (creativity, improvisation, and adaptability)” (p. 257). Over time, disaster researchers have often articulated what they saw as competing views on organized responses to disasters. These approaches are commonly termed the “command and control, problem-solving, or emergent human resources perspectives” (Dynes, 1993, p. 183). While the command and control approach to disaster management sees disaster response mainly in closed system terms, the problem-solving model explicitly recognizes that response activities can never be predicted in advance of actual events. Early work by the Disaster Research Center (DRC) under the direction of Brouillette and Quarantelli (1971) emphasized that entities involved in responding adaptively to disasters vary both in terms of structure and the functions they undertake. Existing organizations maintain their pre-disaster structure (size, membership, organizational arrangements) as well as the tasks they perform. Expanding organizations change their structure, for example, by taking on new members and incorporating other organizational entities but continue to perform their normally assigned tasks. Additionally as the scale and severity of an event increases, response activities tilt more toward emergent forms of organization.