Discourse surrounding the role of science in modern society has been characterized by increasing scrutiny and skepticism. To address this, scientists have increasingly felt a need to share their results and engage with public audiences through public engagement. Historically, public engagement has been based on the deficit model, which attributes public skepticism to a lack of understanding due to limited knowledge. The deficit model has since fallen out of favor, and scholars have called for more democratic and participatory approaches that emphasize interactive dialogue and mutual learning between scientists and public audiences. Yet, there has been debate as to how feasible these more democratic approaches are. Although extant literature on critical public engagement has examined various power dynamics in scientists' interactions with the public, there is a dearth of literature that investigates the ways that institutional forces exert power over scientists in this context. Inattention to this may result in a partial view of power within the context of science and society interactions. Additionally, with the plethora of engagement activities, knowledge about engagement effectiveness is highly context-specific and value-laden. A better understanding of what constitutes effective engagement offers value in terms of the improved design, implementation, and evaluation of public engagement projects. The project also examines how scientists manage boundaries to negotiate the demands of their roles as scientists and engagement practitioners. Results indicate that, although study participants generally describe themselves as power-holders in the context of making critical decisions about the engagement, they recognize that public audiences can affect engagement effectiveness. Moreover, study respondents acknowledged that there is a perceived influence of institutional power through reward, tenure, and promotion policies that significantly affects the nature and quality of engagement. Also, university scientists were motivated to engage because they felt that were ethically obligated and also performed boundary-work in advocating for science. They further performed boundary-work with their justifications for excluding the public in the vetting of the scientific enterprise. Taken together, these results suggest that, although scientists see the value of democratic science and the importance of engagement, there are limits to the extent of this openness. [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://bibliotheek.ehb.be:2222/en-US/products/dissertations/individuals.shtml.]