A method of making a wind turbine blade, the method comprising: providing first and second half shells (12, 14) of the blade, each half shell extending in a spanwise direction between a root end and a tip end and extending in a chordwise direction between a leading edge and a trailing edge; providing a longitudinally-extending shear web comprising a web panel disposed between first and second mounting flanges (28, 30); providing adhesive between the first mounting flange of the shear web and the inner surface of the first half shell; providing adhesive between the second mounting flange of the shear web and the inner surface of the second half shell; the method being characterised by: joining the parts together in a one-stage join up process comprising arranging the second half shell on top of the first half shell and joining the half shells together whilst simultaneously bonding the shear web to the first and second half shells; wherein the method further comprises supporting the shear web relative to the first half shell during the one-stage join up process by means of a plurality of stabilisers attached to the shear web, wherein each stabiliser extends from the shear web and has a foot arranged in contact with the inner surface of the half shell at a location spaced in the chordwise direction from the shear web. providing first and second half shells (12, 14) of the blade, each half shell extending in a spanwise direction between a root end and a tip end and extending in a chordwise direction between a leading edge and a trailing edge; providing a longitudinally-extending shear web comprising a web panel disposed between first and second mounting flanges (28, 30); providing adhesive between the first mounting flange of the shear web and the inner surface of the first half shell; providing adhesive between the second mounting flange of the shear web and the inner surface of the second half shell; the method being characterised by: joining the parts together in a one-stage join up process comprising arranging the second half shell on top of the first half shell and joining the half shells together whilst simultaneously bonding the shear web to the first and second half shells; wherein the method further comprises supporting the shear web relative to the first half shell during the one-stage join up process by means of a plurality of stabilisers attached to the shear web, wherein each stabiliser extends from the shear web and has a foot arranged in contact with the inner surface of the half shell at a location spaced in the chordwise direction from the shear web. joining the parts together in a one-stage join up process comprising arranging the second half shell on top of the first half shell and joining the half shells together whilst simultaneously bonding the shear web to the first and second half shells; wherein the method further comprises supporting the shear web relative to the first half shell during the one-stage join up process by means of a plurality of stabilisers attached to the shear web, wherein each stabiliser extends from the shear web and has a foot arranged in contact with the inner surface of the half shell at a location spaced in the chordwise direction from the shear web.