A bioreactor system for the production of tissue prostheses, the bioreactor system comprising: a bioreactor having a bioreactor inlet port and a bioreactor outlet port, a culture medium reservoir having a reservoir inlet-/outlet port, wherein the bioreactor and reservoir components of the bioreactor system are combined to a single unitary structure; the bioreactor system furthermore comprising a first conduit coupled between the bioreactor inlet port and the reservoir outlet port, a second conduit coupled between the bioreactor outlet port and the reservoir inlet port, pump means (79, 83, 85) operable to pump fluid into and draw fluid out of a pumping chamber defined in the bioreactor to generate a pulsatile flow of culture medium through the reservoir and bioreactor via said first and second conduits, one or more flow meters operable to generate flow rate signals representative of the rate of culture medium flow through one or both of said first and second conduits, and control means arranged to receive said flow rate signals from said one or more flow meters and to control the pump means (79, 83, 85) in response to said received flow rate signals to provide a desired rate of culture medium flow, wherein said bioreactor comprises a plurality of shaped components which when assembled together define:. said pumping chamber, wherein said pumping chamber is split by a movable membrane into a culture medium pumping chamber and a pumping fluid chamber; and wherein said pumping chamber is defined by a hollow base component and a hollow middle component; said culture medium reservoir, wherein the culture medium reservoir is defined by a hollow top component configured to locate on a wall of said hollow middle component, a prosthesis mounting chamber, wherein the culture medium pumping chamber is in fluid communication with the reservoir and the prosthesis mounting chamber, and the prosthesis mounting chamber is in fluid communication with the culture medium pumping chamber and the reservoir, the bioreactor further comprising a first non-return valve for limiting circulation of culture medium within the bioreactor to a flow from the pumping chamber to the reservoir via the prosthesis mounting chamber, and a second non-return valve provided in said wall of said hollow middle component for limiting circulation of culture medium within the bioreactor to a flow from the reservoir to the pumping chamber, wherein the prosthesis mounting chamber is located within said culture medium reservoir. a bioreactor having a bioreactor inlet port and a bioreactor outlet port, a culture medium reservoir having a reservoir inlet-/outlet port, wherein the bioreactor and reservoir components of the bioreactor system are combined to a single unitary structure; the bioreactor system furthermore comprising a first conduit coupled between the bioreactor inlet port and the reservoir outlet port, a second conduit coupled between the bioreactor outlet port and the reservoir inlet port, pump means (79, 83, 85) operable to pump fluid into and draw fluid out of a pumping chamber defined in the bioreactor to generate a pulsatile flow of culture medium through the reservoir and bioreactor via said first and second conduits, one or more flow meters operable to generate flow rate signals representative of the rate of culture medium flow through one or both of said first and second conduits, and control means arranged to receive said flow rate signals from said one or more flow meters and to control the pump means (79, 83, 85) in response to said received flow rate signals to provide a desired rate of culture medium flow, wherein said bioreactor comprises a plurality of shaped components which when assembled together define:.