摘要: This issue of Pharmaceuticals, Policy and Law examines the implications defects in complex defence systems. Host (immunity) to infection is one most rapidly evolving areas medicine. Inherited immunodeficiency diseases are often life threatening therefore impact on both individual family as well society, terms medical financial input required prevent treat serious infections. Even highly technologically advanced countries, these conditions lead significant monetary, ethical social strains it no surprise that a whole this series dedicated group conditions. chapter, provides general introduction Immunity Immunodeficiency Diseases. These immune systems normally protect individuals from myriad microorganisms potentially can cause infection. Failure result disease, possible death, with viruses bacteria fungi. Primary deficiencies intrinsic failure Our knowledge system how go wrong has grown exponentially over last 50 years, largely through development techniques have allowed us understand structure function basic building blocks life, particularly our proteins genes (molecular biology). From understanding only handful ways be defective (immunodeficiency