A total of 10–15% of children undergoing unilateral inguinal hernia repair develop a metachronous contralateral inguinal hernia (MCIH) that necessitates second anesthesia and surgery. Contralateral exploration can be performed to prevent MCIH development. This study investigates (1) factors that promote or hinder the adoption and (de-)implementation of contralateral groin exploration in children ≤ 6 months undergoing unilateral hernia repair and (2) strategies to overcome these barriers. A qualitative interview study was conducted using 14 semi-structured interviews and two focus groups involving healthcare professionals, stakeholders involved from a patients’ perspective and stakeholders at the organizational/policy level. The results show that the effectiveness of surgical treatment and stakeholders’ motivation and attitudes towards the intervention were reported as barriers for implementation, whereas patient and family outcomes and experience and strategies to overcome these barriers were identified as facilitating factors for future implementation. This study is unique in its contributions towards insights into facilitators and barriers for (de-)implementation of contralateral groin exploration in children with a unilateral inguinal hernia. In case the HERNIIA trial shows that contralateral exploration is beneficial for specific patient and family outcomes or a subgroup of children, the results of this study can help in the decision-making process as to whether contralateral exploration should be performed or not.