Humankind has always lived with natural hazards and their consequences. While the frequency and intensity of geological processes may have remained relatively stable, population growth and infrastructure development in areas susceptible to experiencing natural hazards has increased societal risk and the losses experienced from hazard activity. Furthermore, increases in weather-related (e.g., hurricanes, wildfires) hazards emanating from climate change will increase risk in some countries and result in others having to deal with natural hazard risk for the first time. Faced with growing and enduring risk, disaster risk reduction (DRR) strategies will play increasingly important roles in facilitating societal sustainability. This article discusses how readiness or preparedness makes an important contribution to comprehensive DRR. Readiness is defined here in terms of those factors that facilitate people’s individual and collective capability to anticipate, cope with, adapt to, and recover from hazard consequences. This article first discusses the need to conceptualize readiness as comprising several functional categories (structural, survival/direct action, psychological, community/capacity building, livelihood and community-agency readiness). Next, the article discusses how the nature and extent of people’s readiness is a function of the interaction between the information available and the personal, family, community and societal factors used to interpret information and support readiness decision-making. The health belief model (HBM), protection motivation theory (PMT), person-relative-to-event (PrE) theory, theory of planned behavior (TPB), critical awareness (CA), protective action decision model (PADM), and community engagement theory (CET) are used to introduce variables that inform people’s readiness decision-making. A need to consider readiness as a developmental process is discussed and identifies how the variables introduced in the above theories play different roles at different stages in the development of comprehensive readiness. Because many societies must learn to coexist with several sources of hazard, an “all-hazards” approach is required to facilitate the capacity of societies and their members to be resilient in the face of the various hazard consequences they may have to contend with. This article discusses research into readiness for the consequences that arise from earthquake, volcanic, flood, hurricane, and tornado hazards. Furthermore, because hazards transcend national and cultural divides, a comprehensive conceptualization of readiness must accommodate a cross-cultural perspective. Issues in the cross-cultural testing of theory is discussed, as is the need for further work into the relationship between readiness and culture-specific beliefs and processes.