Implementation of effective interventions into clinical practice is slow, in large part, because researchers do not sufficiently attend to the realities of nurses who implement interventions. The aim of the study was to provide an exemplar of how cognitive interviewing-an important and underused method for developing nursing research-can be used to design survey items and assess multilevel implementation factors. We utilized the Consolidated Framework for Implementation Research to create a survey to assess factors that influence how oncology nurses deliver physical activity interventions. Two rounds of cognitive interviews were conducted with five purposively selected oncology nurses to assess survey items' clarity and effectiveness at eliciting desired information. We used a cognitive interviewing coding scheme to code data and revise unclear items. Participants completed the revised survey online and underwent a second interview to provide additional feedback. Seven important changes were made to the survey: how to assess nurses' perceptions of other nurses' beliefs and practices; language to capture data relating to nursing leadership and administration; increased detail to assess factors related to nurses' workplaces; language related to capturing factors related to policy; language to capture data related to equity, disparities, and cultural tailoring; terms replacement with language used by nurses; and strategy to capture data about nurses' knowledge of national physical activity recommendations for cancer survivors. Cognitive interviewing can be applied to develop survey items that capture real-world experiences and perspectives of practicing nurses. This is an essential step in developing nursing interventions that are ready to be implemented and increasing the uptake of evidence-based nursing care. Cognitive interviewing can be used across nursing settings, populations, and interventions to develop understandings of attitudes, attributes, characteristics, and perceptions for a variety of nursing interventions.