Reconstruction of large chest wall defects is challenging. Here we discuss the process of decision-making in planning chest wall reconstruction, considering the requirements of tumor removal, stabilization of the chest wall, and soft tissue coverage, illustrated by a case of a hemi-chest wall defect in a child. Ewing sarcoma measuring 10 × 9 × 13 cm was resected in a 9-year-old boy, followed by stabilization using a Gore-Tex patch. Due to extension of the oncologic resection far into the superomedial quadrant of the chest, tension-free coverage with a classical latissimus-dorsi flap could not be achieved. Integrating the serratus-anterior muscle into the flap creating a chimeric latissimus-dorsi/serratus-anterior flap allowed for excellent soft tissue coverage of the foreign body. As the skin could be preserved, careful incision planning was necessary to allow for best possible exposure during oncologic resection and flap harvest, while ensuring skin vascularization impaired by underlying tumor resection. Two vertical skin incisions were chosen, one presternal and a second in the mid-axillary fold delineating a large bipedicled skin flap. Postoperative recovery was excellent. Solid skin vascularization and adequate soft tissue coverage of the alloplastic material allowed for the patient to receive two cycles of postoperative radiotherapy without developing wound dehiscence. Careful interdisciplinary planning of skin incisions allowed for good exposure for tumor resection and flap harvest while preserving skin vascularization. Choosing a chimeric latissimus-dorsi/serratus-anterior flap provided larger coverage than a classical latissimus-dorsi flap with minimal additional donor site morbidity. Taken together, we here present a pragmatic solution to a complex problem.