Semistructured in-depth qualitative interviews were conducted with caregivers and nurses. Participation in the interview was not required for the infant to be enrolled to use the infant warmer. All interviews were conducted in a private space at the local health center where the person worked. Interviews were carried out in the local language, Kinyarwanda, audio recorded, transcribed, and then translated into English by a professional Rwandan translator. An independent translator back-translated 10% of the interviews into Kinyarwanda, and compared them with the original transcripts for validation. Analysis began with completion of the first interview. Contents were assessed to assure sufficiency of questions used.