BMC Public Health 2006, 6:313 http://www.biomedcentral.com/1471-2458/6/313 in which organizations and inter-organizational networks are located and in which threats first emerge, and 4) the integrated coordination of specific action-sets. An action- set refers, in this case, to a subgroup of organizations in the network that come together purposefully to address a specific public health threat. We see these four factors together influencing system-level public health prepared- ness. Sampling design Our target population for the research is all public health and emergency management-related organizations in Alberta. The construction of the project's sampling frame is based on a stratified, multistage cluster design. The strata are four administrative divisions: (1) provincial- level agencies, (2) sub-provincial administrative agencies, i.e., emergency-management districts (disaster services) and regional health authorities, (3) metropolitan areas, and (4) towns and local areas. Within strata 1–3, the sam- pling frame includes all public health or emergency man- agement organizations, i.e., agencies, departments, or units, within those strata. The fourth stratum will be sub- stratified according to the Alberta Emergency Manage- ment district divisions into 6 geographical areas: (1) northwestern Alberta, (2) northeastern Alberta, (3) north- central Alberta, (4) central Alberta, (5) south-central Alberta, and (6) southern Alberta. From each of the 6 geo- graphical regions, we will draw a proportionate, random sub-sample of towns. For stratum 4, the sampling frame consists of all public health or emergency management- related organizations in those towns randomly selected. The project's frame population will thus consist of those organizations listed in the strata 1–3 sampling frame and those listed in the stratum 4 sampling frame. Phase one: initial qualitative research This study will be conducted in 2 phases: phase 1 qualita- tive and phase 2 quantitative research. Phase 1 is used in part to help identify the organizations responsible for public health and emergency responses and the relevant relationships among them. Initial qualitative research will consist of the analysis of official documents and reports and interviews with key organizational representatives. Government documents and reports will be analyzed to 1) help identify agencies involved in the response system, 2) determine the formal tasks assigned to those agencies, and 3) initially assess the overall level of preparedness and responsiveness for the three case studies. Interviews with Individual Organizational Attributes Inter-Organizational Network Structures Institutional Environments PFHigPurSeys1tems Conceptual Framework PHP Systems Conceptual Framework. Action-Set Coordination Public Health Preparedness Page 3 of 5 (page number not for citation purposes)