As efforts to develop new applications of engineered nanoscale materials (ENMs) continue to grow, so too has interest in the environmental, health, and safety (EHS) implications of these materials. However, thorough evaluation and interpretation of such implications could require substantial resources (e.g., estimated as >$120 million per year in federal funding [2013][2014][2015][2016][2017]. A structured, strategic approach for transparently planning research would support improved linkages between ENM research and risk assessments, and thereby enhance the utility of financial and other resources for EHS studies of ENMs. For this reason, we applied Comprehensive Environmental Assessment (CEA) as an approach to provide transparent input into research planning for 2 types of ENMs: nanoscale titanium dioxide and nanoscale silver. For each of these CEA applications, we employed a collective judgment method known as Nominal Group Technique (NGT) in 2 workshops sponsored by the US Environmental Protection Agency (USEPA). The objective of this paper is to present the outcomes of these CEA applications in the context of how our methodology can inform future efforts to identify collective goals in science (e.g., research priorities) through structured decision support approaches. Outcomes include clear lists of research priorities for each ENM developed through transparently engaging stakeholders having diverse technical and sector perspectives. In addition, we identified several procedural aspects that could be refined, including emphasizing breakout group interactions, identifying broad information priorities before more detailed research questions, and using rating rather than ranking prioritization methods. Beyond the research directions identified for specific ENMs, lessons learned about engaging stakeholders in research planning are expected to inform future research planning efforts for ENMs and other emerging materials across the scientific community. Integr Environ Assess Manag 2014;9999:XX-XX. © 2014 SETAC