This dissertation, a three-paper set, explored whether the process skills-based approach to nature of science instruction improves teachers' understandings, intentions to teach, and instructional practice related to the nature of science. The first paper examined the nature of science views of 53 preservice science teachers before and after a year of secondary science methods instruction that incorporated the process skills-based approach. Data consisted of each participant's written and interview responses to the Views of the Nature of Science (VNOS) questionnaire. Systematic data analysis led to the conclusion that participants exhibited statistically significant and practically meaningful improvements in their nature of science views and viewed teaching the nature of science as essential to their future instruction. The second and third papers assessed the outcomes of the process skills-based approach with 25 inservice middle school science teachers. For the second paper, she collected and analyzed participants' VNOS and interview responses before, after, and 10 months after a 6-day summer professional development. Long-term retention of more aligned nature of science views underpins teachers' ability to teach aligned conceptions to their students yet it is rarely examined. Participants substantially improved their nature of science views after the professional development, retained those views over 10 months, and attributed their more aligned understandings to the course. The third paper addressed these participants' instructional practices based on participant-created video reflections of their nature of science and inquiry instruction. Two participant interviews and class notes also were analyzed via a constant comparative approach to ascertain if, how, and why the teachers explicitly integrated the nature of science into their instruction. The participants recognized the process skills-based approach as instrumental in the facilitation of their improved views. Additionally, the participants saw the nature of science as an important way to help students to access core science content such as the theory of evolution by natural selection. Most impressively, participants taught the nature of science explicitly and regularly. This instruction was student-centered, involving high levels of student engagement in ways that represented applying, adapting, and innovating on what they learned in the summer professional 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.]