A method of producing an object, the method comprising: providing a mould tool having a mould surface; applying uncured composite material to the mould surface of the mould tool so as to form an assembly; curing the assembly so as to cure the uncured composite material and mould the uncured composite material against the mould surface, thereby producing cured composite material having a surface that is substantially the same shape as and contiguous with the mould surface; providing a digital model of at least part of the object to be produced, wherein the digital model specifies a first surface of the object to be produced, a second surface of the object to be produced, and a position of the second surface relative to the first surface; and the first surface is substantially the same shape as the mould surface; and while maintaining the position of the cured composite material (12'0 relative to the mould surface, machining, by a router, using the digital model, a further surface of the cured composite material, thereby producing the object; wherein the cured composite material is machined in such a way that: the further surface of the cured composite material is substantially the same shape as the second surface, and the position of the further surface of the cured composite material relative to the mould surface is substantially the same as the position of the second surface relative to the first surface wherein the object is an aircraft panel for forming at an external skin of at least part of an aircraft; and wherein the first surface is an outer mould line of the at least part of the aircraft and the second surface is an inner mould line of the at least part of the aircraft. providing a mould tool having a mould surface; applying uncured composite material to the mould surface of the mould tool so as to form an assembly; curing the assembly so as to cure the uncured composite material and mould the uncured composite material against the mould surface, thereby producing cured composite material having a surface that is substantially the same shape as and contiguous with the mould surface; providing a digital model of at least part of the object to be produced, wherein the digital model specifies a first surface of the object to be produced, a second surface of the object to be produced, and a position of the second surface relative to the first surface; and the first surface is substantially the same shape as the mould surface; and the digital model specifies a first surface of the object to be produced, a second surface of the object to be produced, and a position of the second surface relative to the first surface; and the first surface is substantially the same shape as the mould surface; and while maintaining the position of the cured composite material (12'0 relative to the mould surface, machining, by a router, using the digital model, a further surface of the cured composite material, thereby producing the object; wherein the cured composite material is machined in such a way that: the further surface of the cured composite material is substantially the same shape as the second surface, and the position of the further surface of the cured composite material relative to the mould surface is substantially the same as the position of the second surface relative to the first surface wherein the object is an aircraft panel for forming at an external skin of at least part of an aircraft; and wherein the first surface is an outer mould line of the at least part of the aircraft and the second surface is an inner mould line of the at least part of the aircraft. the further surface of the cured composite material is substantially the same shape as the second surface, and the position of the further surface of the cured composite material relative to the mould surface is substantially the same as the position of the second surface relative to the first surface wherein the object is an aircraft panel for forming at an external skin of at least part of an aircraft; and wherein the first surface is an outer mould line of the at least part of the aircraft and the second surface is an inner mould line of the at least part of the aircraft.