Abstract: This invention relates to a new and improved design associated with the fabrication and construction of a needleless transfer system wherein through the use of a unique valve mechanism there is avoided the necessity to utilize a needle in conjunction with a syringe for purposes of transferring and/or injecting a liquid medium from one environment into another environment. By having the valve mechanism comprise a hollow enclosure which has contained therein a compressible structure which acts both as a filter and as a mechanism to allow for the selective flow of a liquid medium through the system in a singular direction, the capabilities of the needleless transfer system are achieved.