Immunodeficiency in children represents a multifaceted spectrum of disorders characterized by a compromised immune system, impeding the body's ability to defend against infections and diseases. This complex array of conditions arises from a myriad of genetic, acquired, or secondary factors that collectively impair the functioning of the immune system during the crucial stages of childhood development. At its core, immunodeficiency in children manifests as a deficiency in the production, maturation, or functionality of key immune components such as antibodies, T cells, and other immune cells. Primary immunodeficiencies, often stemming from genetic mutations affecting various immune pathways, present early in life and exhibit a diverse range of clinical manifestations, including recurrent infections, delayed wound healing, and increased susceptibility to opportunistic pathogens. Conversely, secondary immunodeficiencies may emerge due to environmental factors, underlying medical conditions, or therapeutic interventions like chemotherapy, placing an additional burden on the Paediatric immune system. The clinical landscape of immunodeficiency in children is further complicated by the intricate interplay between the innate and adaptive immune responses, making accurate diagnosis and tailored treatment approaches pivotal. Diagnostic modalities encompass a comprehensive assessment of immunoglobulin levels, lymphocyte subsets, and functional assays, while treatment strategies vary from antimicrobial prophylaxis and immunoglobulin replacement therapy to hematopoietic stem cell transplantation for severe cases. As the field advances, ongoing research endeavors focus on unraveling the genetic underpinnings of primary immunodeficiencies, refining diagnostic algorithms, and developing innovative therapeutic interventions to enhance the quality of life for children grappling with immunodeficiency challenges. The management of immunodeficiency in children demands a collaborative effort involving Paediatricians, immunologists, geneticists, and other allied healthcare professionals, aiming not only to alleviate the immediate health threats but also to foster a comprehensive understanding of the intricate immune dysregulations in order to pave the way for improved long-term outcomes and a brighter future for these resilient young individuals.