A reconstitution assembly comprising: (a) a housing (12, 20, 30) having a generally cylindrical shape; (b) a first container disposed within the housing and configured to be axially displaced relative to the housing (12, 20, 30), the first container having a first opening sealed with a first seal cap; (c) a second container disposed within the housing having a second opening sealed with a second seal cap, wherein the first container is arranged within the housing coincident to the second container; (d) a transfer set assembly disposed within the housing and between the first container and the second container, the transfer set assembly configured to fluidly access first contents through the first seal cap of the first container and fluidly access second contents through the second seal cap of the second container; and (e) a triggering mechanism configured to ensure that the first contents of the first container are accessed by the transfer set assembly before the second contents of the second container are accessed by the transfer set assembly, the triggering mechanism having a base portion in contact with the second container and a plurality of fingers extending from the base portion, the triggering mechanism operable in an unactivated state and an activated state, wherein: (i) in the unactivated state, the plurality of radially spaced fingers engage with the housing (12, 30) to prevent axial displacement of the second container relative to the housing (12, 20, 30) and the transfer set assembly; and (ii) in the activated state: first, the first container is axially displaced relative to the housing and the transfer set assembly so that the transfer set assembly pierces the first seal cap to access the first contents, the first container then causing the trigger fingers to disengage from the housing after the transfer set assembly has accessed the first contents, second, the second container is axially displaced relative to the housing and the transfer set assembly so that the transfer set assembly pierces the second seal cap to access the second contents. (a) a housing (12, 20, 30) having a generally cylindrical shape; (b) a first container disposed within the housing and configured to be axially displaced relative to the housing (12, 20, 30), the first container having a first opening sealed with a first seal cap; (c) a second container disposed within the housing having a second opening sealed with a second seal cap, wherein the first container is arranged within the housing coincident to the second container; (d) a transfer set assembly disposed within the housing and between the first container and the second container, the transfer set assembly configured to fluidly access first contents through the first seal cap of the first container and fluidly access second contents through the second seal cap of the second container; and (e) a triggering mechanism configured to ensure that the first contents of the first container are accessed by the transfer set assembly before the second contents of the second container are accessed by the transfer set assembly, the triggering mechanism having a base portion in contact with the second container and a plurality of fingers extending from the base portion, the triggering mechanism operable in an unactivated state and an activated state, wherein: (i) in the unactivated state, the plurality of radially spaced fingers engage with the housing (12, 30) to prevent axial displacement of the second container relative to the housing (12, 20, 30) and the transfer set assembly; and (ii) in the activated state: first, the first container is axially displaced relative to the housing and the transfer set assembly so that the transfer set assembly pierces the first seal cap to access the first contents, the first container then causing the trigger fingers to disengage from the housing after the transfer set assembly has accessed the first contents, second, the second container is axially displaced relative to the housing and the transfer set assembly so that the transfer set assembly pierces the second seal cap to access the second contents. (i) in the unactivated state, the plurality of radially spaced fingers engage with the housing (12, 30) to prevent axial displacement of the second container relative to the housing (12, 20, 30) and the transfer set assembly; and (ii) in the activated state: first, the first container is axially displaced relative to the housing and the transfer set assembly so that the transfer set assembly pierces the first seal cap to access the first contents, the first container then causing the trigger fingers to disengage from the housing after the transfer set assembly has accessed the first contents, second, the second container is axially displaced relative to the housing and the transfer set assembly so that the transfer set assembly pierces the second seal cap to access the second contents. first, the first container is axially displaced relative to the housing and the transfer set assembly so that the transfer set assembly pierces the first seal cap to access the first contents, the first container then causing the trigger fingers to disengage from the housing after the transfer set assembly has accessed the first contents, second, the second container is axially displaced relative to the housing and the transfer set assembly so that the transfer set assembly pierces the second seal cap to access the second contents.