This research explores self-awareness, feedback exchange, and interpersonal communication among seafarers through the application of the Johari Window model. Using behavioral observations and informal interviews with 24 crew members representing all shipboard departments, the vessel’s Captain evaluated how individuals share personal information, respond to feedback, and interact with colleagues. The results indicate clear variations in dominant Johari Window quadrants according to rank and department—officers generally exhibit greater openness, while lower-ranking and engine room personnel tend to occupy more hidden or blind areas. The study concludes that applying the Johari Window framework can significantly improve leadership effectiveness, team collaboration, and psychological safety within maritime environments.