aim: the purpose of this systematic review was to critically examine the literature about the effectiveness of rooming-in compared to traditional care settings such as the neonatal intensive care unit (nicu) for newborns with neonatal abstinence syndrome (nas). background: nas is a multi-system disorder observed in newborns experiencing withdrawal following in-utero opioid exposure. rooming-in may be beneficial to newborns with nas as outcomes may reduce the need for pharmacologic treatment, the duration of pharmacologic treatment, and shorten length of stay (los). although the studies support rooming-in, information in this area of research is limited. based on the little evidence known, rooming-in may provide beneficial outcomes for newborns with nas symptoms. therefore examining the outcomes of nas and rooming-in may be insightful to the contribution of research in this area of nas. method: a systematic search exploring the effects of rooming-in and nas in newborns was conducted using the following electronic databases: pubmed, proquest, psychoinfo, ovid joanna briggs institute of systematic reviews, cinahl, nursing and allied health, evidence-based medicine, web of science, cochrane database of systematic review, dare and medline (embase). studies were eligible for inclusion in the review if they fulfilled the following criteria: (1) reported outcome data for newborns with nas and rooming-in care, (2) primary studies, (3) quantitative studies with a comparison group, (4) peer-reviewed, and (5) were published in english. selected studies were assessed by two appraisers using the jbi standardized critical appraisal checklist for cohort studies. findings: the search identified two hundred sixteen (n = 216 studies). an additional two studies were retrieved through a forward citation search. following removal of studies that did not meet the inclusion criteria, six studies remained for the systematic review. the results from this review suggest that rooming-in has the potential to improve nas outcomes including: a decreased need for pharmacologic treatment, a shorter duration of pharmacologic treatment, a reduction in hospital stay, and healthcare cost savings. these findings support the need for rooming-in to care for newborn with nas symptoms. conclusion: the findings from this systematic review suggest that rooming-in for newborns with nas was effective in reducing the duration of pharmacologic treatment, need for pharmacologic treatment, and length of hospital stay compared to traditional care settings. rooming-in should be explored as a care model for select newborns however further investigation is required with larger sample sizes and a more detailed description of rooming-in in order to gain further insight.