Background: Surgical nursing within humanitarian contexts is complex, sporadically described in literature and little understood. Aim: To achieve a deeper understanding of the lived experience of New Zealand nurses providing humanitarian aid within surgical settings and war zones in developing countries. Method: In-depth conversational interviews were undertaken with four New Zealand nurses whose humanitarian experience lay in general surgical, military, and intensive care settings. A qualitative descriptive method as described by Sandelowski, informed by van Manen’s phenomenology in terms of analysis, was used. Results: Specialized knowledge and nursing expertise are recognized to be essential but not sufficient for humanitarian work. Understanding local cultures contributes to positive feelings about work effectiveness. Themes included feeling anxious and misunderstood, practicing differently, and adjusting to life back home. Discussion: This study highlights the need to better prepare nurses who volunteer for humanitarian work, with implications for recruiting organizations, educators, and clinicians.