The study consists of two parts. Part one examined the clinical use of the multimodal neurologic enhancement music therapy intervention (MNE) in the NICU and compared clinical outcomes of infants who received MNE with those who did not. A post hoc analysis was utilized to examine clinical data of infants from 2018 who were hospitalized in a single NICU unit. Subjects (N = 530) were infants born preterm, which is defined as less than 37 weeks postmenstrual age. Demographics were compared between the infants who did and did not receive NICU-MT. There was a significant difference between the groups with infants receiving NICU-MT being born younger and at a lower birthweight, and with more acute diagnoses indicating referral for NICU-MT going to more acute preterm infants. In order to compare clinical outcomes, the researcher matched infants based on sex, gestational age at birth, birthweight category, number of acute diagnoses, diagnoses of bronchopulmonary disease, and diagnoses of a feeding problem. Clinical outcomes for the matched infants (n=55 in each group) were compared between the two groups, showing that infants who received NICU-MT went home sooner, gained more weight per day, and ended oxygen treatment sooner. The benefits of NICU-MT were the greatest for infants born extremely preterm or at an extremely low birthweight. Part two was a two-year follow-up study that examined developmental outcomes in the domains of communication, gross motor, fine motor, problem solving, and socio-emotional skills of infants at two years of age who received MNE in the NICU compared to normative data for term infants. Subjects (N = 30) were toddlers who were born premature (<37 weeks), hospitalized in a neonatal intensive care unit after birth, and received the MNE intervention. Parents completed developmental questionnaires about their toddlers who were two years adjusted age. Developmental outcomes were measured using two standardized developmental questionnaires. The Ages & Stages Questionnaire, 3rd edition, (ASQ-3) was used to assess overall developmental outcomes (Squires, 2009). The Ages and Stages Questionnaire: Social & Emotional, 2nd edition, (ASQ:SE2) was used to assess behavioral and social-emotional outcomes (Squires et al., 2015). Outcomes on the ASQ-3 showed that the majority of follow-up infants were in the no- to low-risk category in all domains of communication, gross motor, fine motor, problem solving, and personal social skills. The follow-up infants exhibited better outcome scores than did the normative sample on the ASQ:SE2 with a lower median score and fewer infants identified as being at high risk for a social-emotional delay. Regression analyses indicated that the number of MNE intervention sessions did not significantly predict the outcome scores for any domain on the ASQ-3 or the total score on the ASQ:SE2. However, the number of music therapy sessions did significantly predict the outcome scores on the communication and fine motor domains (p < .05) in the multiple linear regression analyses. These outcomes warrant the need for further research on the potential long-term impacts of NICU-MT interventions.