A fall arrest harness for arresting the fall of a person working at height comprising: - a pair of leg straps (12,13) for encircling the thighs of a wearer of said fall arrest harness and for locating the fall arrest harness on a wearer of said harness; - a first shoulder strap, configured to extend over the left shoulder and left chest region of said wearer, and a second shoulder strap, configured to extend over the right shoulder and right chest region of said wearer; - a lanyard connection member for connection to a safety lanyard; - one or more extension straps (16,17), the lanyard connection member being connected to said shoulder straps (4,5) via said one or more extension straps (16,17); and - a rear section, the rear section extending between said pair of leg straps (12,13) and said first and second shoulder straps and having a seat portion and a back portion, the seat portion being adapted to lie across the sub-pelvic region or seat of the wearer, and the back portion being adapted to overlie at least a portion of the back of the wearer, characterised in that: - the first shoulder strap extends between a left side region of the seat portion and an upper region of the back portion; - the second shoulder strap extends between a right side region of the seat portion and an upper region of the back portion; the lanyard connection member is releasably attachable to the back portion of the rear section at a dorsal position by releasable securing means (21,22) and is separately connected to both the first and second shoulder straps via said one or more extension straps (16,17) at, respectively, said left and right chest regions; and - the lanyard connection member is detachable from the back portion when a tensile force applied to the lanyard connection member exceeds a predetermined threshold such that in the event of a fall the lanyard connection member separates from the back portion, whereby the one or more extension straps (16,17) and the lanyard connection member automatically move to a sternal suspension position to suspend the wearer from both of said first and second shoulder straps in a supine position with the weight of the wearer being borne by the seat portion and the back portion of the rear section and being transferred to the lanyard connection member via both said first and second shoulder straps and the one or more extension straps (16,17) with none of said weight being transferred by the leg straps (12,13). - a pair of leg straps (12,13) for encircling the thighs of a wearer of said fall arrest harness and for locating the fall arrest harness on a wearer of said harness; - a first shoulder strap, configured to extend over the left shoulder and left chest region of said wearer, and a second shoulder strap, configured to extend over the right shoulder and right chest region of said wearer; - a lanyard connection member for connection to a safety lanyard; - one or more extension straps (16,17), the lanyard connection member being connected to said shoulder straps (4,5) via said one or more extension straps (16,17); and - a rear section, the rear section extending between said pair of leg straps (12,13) and said first and second shoulder straps and having a seat portion and a back portion, the seat portion being adapted to lie across the sub-pelvic region or seat of the wearer, and the back portion being adapted to overlie at least a portion of the back of the wearer, characterised in that: - the first shoulder strap extends between a left side region of the seat portion and an upper region of the back portion; - the second shoulder strap extends between a right side region of the seat portion and an upper region of the back portion; the lanyard connection member is releasably attachable to the back portion of the rear section at a dorsal position by releasable securing means (21,22) and is separately connected to both the first and second shoulder straps via said one or more extension straps (16,17) at, respectively, said left and right chest regions; and - the lanyard connection member is detachable from the back portion when a tensile force applied to the lanyard connection member exceeds a predetermined threshold such that in the event of a fall the lanyard connection member separates from the back portion, whereby the one or more extension straps (16,17) and the lanyard connection member automatically move to a sternal suspension position to suspend the wearer from both of said first and second shoulder straps in a supine position with the weight of the wearer being borne by the seat portion and the back portion of the rear section and being transferred to the lanyard connection member via both said first and second shoulder straps and the one or more extension straps (16,17) with none of said weight being transferred by the leg straps (12,13).