Background: Nurses’ roles are an important aspect of their approaches to pain management and monitoring in the post-operative phase of recovery in a surgical ward. A barrier to successful pain management may be the nurse’s perceptions of the patient in pain, which are confounded by the patterns of communication within individual contexts. We need to study, grasp and understand the complexities of the pain management practice within the context of the surgical ward in order to be able to improve the practices and design appropriate interventions to help patients in need. Objective: The purpose of this study was to explore nurses’ postoperative pain management practices. Methods: This qualitative triangulation study was conducted in a surgical ward at a public hospital in Bangkok (Thailand) from 2012 to 2015. We applied four qualitative methods in the study: 1) observations in a postoperative pain management setting (100 hours); 2) in-depth interviews (12 nurses), 3) three focus group discussions (18 nurses), and 4) narratives relating to 69 critical incidents gathered during recurrent visits over a period of ten weeks (9 nurses). Content analysis, as outlined in grounded theory, was applied. Results: The 40 nursing staff made their observations of the participants by conducting go-along interviews while they worked in the surgical field. The group of nurses comprised of 20 females and 4 males, age-ranged between 21-49 years of age, and their nursing experience ranged from 1-28 years. From our analysis, nurses verified patients’ pain by using double- and triple-control methods to document and record it, thus managing pain by administrative procedures rather than being proactive in providing pain relief. Therefore, communication and information about the patients’ pain and subsequent treatment of postoperative pain caused delays that may hamper the adequate use of available analgesics for pain relief. Levels of experience in communicating between nurses, other professionals, and patients were a main cause of delays in treating and managing pain. Conclusion: The complex communication system that would improve the communication ways leads to better standards of practice and quality of care.