Jeff Ernst, Kelly Josh, Eric L. Olson, Kristen Sample and Ricardo Zúñiga, the authors of this report, interviewed current and former US officials and development practitioners who carried out US assistance in the 2014–19 period, as well as experts and beneficiaries in the Northern Triangle, to gain their insights regarding the overall efficacy of this assistance. Ideally, the lessons learned through this exercise will inform current and future efforts to promote sustainable, positive change in the three countries.