Oncological surgery in pediatric patients, while crucial for removing malignant tumors, often involves extensive resection that may lead to significant physical, psychological, and functional challenges. Such procedures can cause impaired mobility, loss of organ function, and cosmetic sequelae that become more pronounced as the child grows. Reconstructive surgery plays a vital role in restoring both form and function, improving aesthetic outcomes, supporting physical rehabilitation, and enhancing psychological well-being. This chapter emphasizes the importance of early, proactive planning in addressing the debilitating effects of oncological resections, outlining strategies for damage limitation in surgical planning, as well as practical examples of both immediate and delayed reconstruction. A multi-disciplinary approach to planning and post-operative care, involving surgeons, oncologists, and other specialists, is essential for tailoring the best reconstructive solutions for pediatric patients. Key considerations include preserving future growth potential, particularly in cases involving radiotherapy, large soft tissue and bony defects, and limb and head and neck reconstructions. This chapter focuses primarily on autologous tissue reconstruction, though alternative options such as prostheses and alloplastic materials are briefly acknowledged. This chapter also highlights important technical tips, pearls for successful procedures, common pitfalls to avoid, as well as post-operative care considerations and a discussion on the management of complications to ensure the best long-term results.