A drug delivery system comprising: a fluid store for storing a medicament; a first tubing having an inlet in fluid communication connection with said fluid store so that the medicament flows from said fluid store through said first tubing, said first tubing having an outlet first connector of a given configuration that enables said outlet first connector to only be connectable with a counterpart connector that has a configuration complementary to said given configuration and prevents said outlet first connector from connecting with a counterpart connector that has a conventional luer configuration or a configuration not complementary to said given configuration; a tube retainer device having an inlet second connecter (10, 8f) and an outlet, a tube guide extending along said tube retainer device to be in communication with the inlet second connector (10, 8f) and the outlet, a second tubing inserted into the outlet and extends through the tube guide to be in fluid communication with the inlet second connector (10, 8f) for interfacing with a patient, the tube retainer device having an open position and a closed position, the second tubing enveloped by the tube guide being fixedly but non occludedly retained by the tube retainer device when the tube retainer device is in its closed position, the inlet second connector having a complementary configuration to said given configuration of said outlet first connector of said first tubing so that said inlet second connector (10, 8f) is connectable to said outlet first connector; and an extension tubing having a first end fitted with a third connector and a second end fitted with a fourth connector, said third and fourth connecters (22, 24) each having a configuration complementary to said given configuration so that said third connector is connectable with said outlet first connector of the first tubing but not with a counterpart connector of a conventional luer configuration and said fourth connector is connectable with said second connector of the tube retainer device but not with a counterpart connector of a conventional luer configuration, said extension tubing connected to said first tubing via the coupling of said first connector and said third connector and to said tube retainer device via the coupling of said second connector (10, 8f) and said fourth connector to establish a fluid through path from said fluid store to said second tubing; and a one way valve integrated to either of said third and fourth connectors (22, 24) to prevent back flow of the medicament so as to ensure that the medicament only flows unidirectionally from the fluid store to the patient. a fluid store for storing a medicament; a first tubing having an inlet in fluid communication connection with said fluid store so that the medicament flows from said fluid store through said first tubing, said first tubing having an outlet first connector of a given configuration that enables said outlet first connector to only be connectable with a counterpart connector that has a configuration complementary to said given configuration and prevents said outlet first connector from connecting with a counterpart connector that has a conventional luer configuration or a configuration not complementary to said given configuration; a tube retainer device having an inlet second connecter (10, 8f) and an outlet, a tube guide extending along said tube retainer device to be in communication with the inlet second connector (10, 8f) and the outlet, a second tubing inserted into the outlet and extends through the tube guide to be in fluid communication with the inlet second connector (10, 8f) for interfacing with a patient, the tube retainer device having an open position and a closed position, the second tubing enveloped by the tube guide being fixedly but non occludedly retained by the tube retainer device when the tube retainer device is in its closed position, the inlet second connector having a complementary configuration to said given configuration of said outlet first connector of said first tubing so that said inlet second connector (10, 8f) is connectable to said outlet first connector; and an extension tubing having a first end fitted with a third connector and a second end fitted with a fourth connector, said third and fourth connecters (22, 24) each having a configuration complementary to said given configuration so that said third connector is connectable with said outlet first connector of the first tubing but not with a counterpart connector of a conventional luer configuration and said fourth connector is connectable with said second connector of the tube retainer device but not with a counterpart connector of a conventional luer configuration, said extension tubing connected to said first tubing via the coupling of said first connector and said third connector and to said tube retainer device via the coupling of said second connector (10, 8f) and said fourth connector to establish a fluid through path from said fluid store to said second tubing; and a one way valve integrated to either of said third and fourth connectors (22, 24) to prevent back flow of the medicament so as to ensure that the medicament only flows unidirectionally from the fluid store to the patient.