It is universally known that breastfeeding provides a broad spectrum of nutritional and non-nutritional advantages to the developing infant. Nonnutritive protecting potentials of breast milk towards different infections and non-infectious diseases are still attracting the attention of researchers in different specialties. The neonate, who is suddenly exposed to a wide variety of organisms, is in dire need of protection, enhancement and education of his immature immune system to encounter these organisms. The lactating mammary gland is an integral part of the common mucosal immune system which stands as a sentinel in combating pathogens that enter the body via the mucosal route. The common mucosal immune system also competently controls tolerance mechanisms to innocent proteins and is involved in surveillance of carcinogensis. The diverse roles of general mucosal immunity are nearly well established but the specialised functions of breast tissue and breast milk in boosting the immune responses need more emphasis and highlighting. The detailed understanding and evaluation of breast milk as an immunological tool is reviewed within the domain of the diverse activities of the common mucosal immune system.