S E T T ING: In 2012, Peru's National TB Program (NTP) reported approximately 2400 incident cases of tuberculosis (TB) disease in children aged ,15 years. Peru's TB burden is concentrated in the Lima metropolitan area, particularly in poor districts such as El Agustino and La Victoria, where this study was conducted. OBJECTIVE : To identify barriers to the treatment of childhood tuberculous infection and TB disease in Lima from the perspective of front-line providers and patients' families. D E S I G N : We conducted 10 semi-structured focus groups with 53 purposefully sampled primary care providers, community health workers, and parents/ guardians of pediatric TB patients. We also completed nine in-depth interviews with National TB Program administrators and pulmonologists specializing in TB. Two authors performed inductive thematic analysis and identified emerging themes. RESULT S : Four main treatment barriers emerged from the data: 1) dosing errors, 2) time-and labor-intensive preparation and administration of medications, 3) provider concern that isoniazid preventive therapy (IPT) generates isoniazid resistance, and 4) poor adherence to IPT. CONCLUS ION: Our findings highlight the urgent need for child-friendly formulations, provider and parent/ guardian education about IPT, and strategies to promote adherence to IPT, including support and supervision by health workers and/or regimens with fewer doses.