Co-sleeping can provide numerous benefits for both the parent(s) and the infant. Perhaps the greatest advantage lies in its promotion of breastfeeding, an act widely recognized for its benefits to both the mother and infant. However, risks also are associated with co-sleeping, prompting many researchers to examine the safety of its practice. Pediatric nurse practitioners need to be informed on issues related to co-sleeping in order to educate parents regarding its risks and benefits, to assess the safety of an established sleeping environment, and to be aware of its prevalence in their patient populations. A review of the literature is presented to inform pediatric nurse practitioners about varied definitions of co-sleeping, the reasons why some parents engage in the practice, cultural preferences for co-sleeping, associated risks and benefits, and its relationship to breastfeeding.