Objective: To assess the knowledge, attitudes and practices of mothers regarding exclusive breastfeeding in infants, admitted in PIMS, Islamabad. Study Design: Descriptive qualitative study design based on in-depth interviews. Place and Study Duration: It was carried out from December 2015 to May 2016 involving mothers of infants admitted in PIMS Islamabad. Materials and Methods: Data was collected through in-depth interviews from the mothers of infants till the saturation of ideas, which was came at the thirtieth respondent. The collected data was analyzed manually. Verbatim notes were taken and interviews were recorded. After transcribing the data, nodes and sub-nodes were developed and on the basis of them, themes were generated. Results: The results of the study showed that most of the mothers knew the advantages of breast feeding and its importance for the health of the infants. The main reason behind this was the cultural practices, running in the families for years as well as the myths of elderly at homes, who were the main decision makers. Conclusion: The study gave a basic level of knowledge, attitude and practices of mothers about exclusive breast feeding. Breastfeeding is a natural and beneficial source of nutrition and provides the healthiest start for an infant.