Apparatus for providing a fluid passageway into an individual, the apparatus comprising: a port (12, 127, 212) in fluid communication with the atmosphere; a catheter (4, 104, 204) having a proximal end arranged to be inserted into the body of an individual and having a distal end; a one-way valve (18, 118, 218); and a fluid passage switch (24, 124, 224), the apparatus being characterised in that: the fluid passage switch is reversibly movable between a first position in which the distal end of the catheter is in fluid communication with the port, the port and the catheter are axially aligned and in which the fluid passage switch and the port are arranged to receive a needle therein, such that whenever the fluid passage switch is in the first position a needle can be introduced into the catheter via the port and fluid passage switch, and a second position in which the distal end of the catheter is in exclusive fluid communication with the one-way valve and in which the one-way valve is arranged to permit fluid flow therethrough whenever there is a pressure differential of at least a predetermined value across the valve, such that whenever the fluid passage switch is in the second position aspiration of fluid through the catheter and subsequently the one-way valve is permitted. a port (12, 127, 212) in fluid communication with the atmosphere; a catheter (4, 104, 204) having a proximal end arranged to be inserted into the body of an individual and having a distal end; a one-way valve (18, 118, 218); and a fluid passage switch (24, 124, 224), the apparatus being characterised in that: the fluid passage switch is reversibly movable between a first position in which the distal end of the catheter is in fluid communication with the port, the port and the catheter are axially aligned and in which the fluid passage switch and the port are arranged to receive a needle therein, such that whenever the fluid passage switch is in the first position a needle can be introduced into the catheter via the port and fluid passage switch, and a second position in which the distal end of the catheter is in exclusive fluid communication with the one-way valve and in which the one-way valve is arranged to permit fluid flow therethrough whenever there is a pressure differential of at least a predetermined value across the valve, such that whenever the fluid passage switch is in the second position aspiration of fluid through the catheter and subsequently the one-way valve is permitted. the fluid passage switch is reversibly movable between a first position in which the distal end of the catheter is in fluid communication with the port, the port and the catheter are axially aligned and in which the fluid passage switch and the port are arranged to receive a needle therein, such that whenever the fluid passage switch is in the first position a needle can be introduced into the catheter via the port and fluid passage switch, and a second position in which the distal end of the catheter is in exclusive fluid communication with the one-way valve and in which the one-way valve is arranged to permit fluid flow therethrough whenever there is a pressure differential of at least a predetermined value across the valve, such that whenever the fluid passage switch is in the second position aspiration of fluid through the catheter and subsequently the one-way valve is permitted.