The purpose of this study was to understand how Thai scientists from four disciplines viewed nature of science (NOS). The sixteen participating scientists were chosen from the areas of chemistry, physics, biology/life sciences, and geology/earth sciences and were separated into novice and expert groups. The scientists' understandings about NOS were compared within and among the science groups as well as within and between novices and experts. All participants in the study had an opportunity to voice their opinions about the seven aspects of NOS that science educators in the United States have agreed should be taught in K-12 science classrooms. The scientists' views were found to be neither informed nor naive but were a mix between the two. Many scientists' responses showed more naive views with respect to tentativeness, subjectivity, social and cultural embeddedness, and the relationship between scientific theories and laws. The scientists' views about NOS differed with few observable patterns within or across disciplines. The novices' and experts' views of aspects of NOS were not substantially different. The scientists from both groups generally shared mixed viewpoints. Even though a few discipline specific patterns emerged from this study, cross disciplinary aspects of NOS in integrated science instruction is suggested rather than establishing particular concepts of NOS for each discipline so as to reduce complexity. Representatives of both novice and expert groups might be recruited to participate in developing new science curricula, teaching materials, and science teacher training programs. In addition, other factors need to be considered such as their knowledge of NOS, their willingness to get involved in science education at the school level or teacher education program, and their willingness to cooperate in the multi-step tasks of curriculum development. [The dissertation citations contained here are published with the permission of ProQuest LLC. Further reproduction is prohibited without permission. Copies of dissertations may be obtained by Telephone (800) 1-800-521-0600. Web page: http://www.proquest.com/en-US/products/dissertations/individuals.shtml.]