An undercut clip (UCC1, UCC2) anchor system for anchoring cladding panels to a structure, the system comprising: a horizontal rail (H3, H3.1, H4) having a mounting surface for mounting to the structure, an upper upward projection spaced a first distance from the mounting surface, and a lower upward projection spaced a second distance from the mounting su rface, characterised in that the second distance is greater than the first distance; and an undercut clip (UCC1, UCC2) having a substantially planar panel attachment portion, a first mounting wall portion, a second mounting wall portion, a first bridge portion connecting one end of the panel attachment portion and a first end of the first mounting wall portion, a second bridge portion connecting a second end of the first mounting wall portion and one end of the second mounting wall portion, a first mounting slot formed between the panel attachment portion and the first mounting wall portion, and a second mounting slot formed between the first mounting wall portion and the second mounting wall portion; wherein the undercut clip (UCC1, UCC2) is adapted to be selectively mounted to the horizontal rail (H3, H3.1, H4) in one of a first position in which the upper upward projection is located in the second mounting slot, and a second position in which the lower upward projection is located in the first mounting slot, for anchoring a cladding panel, and wherein the undercut clip (UCC1, UCC2) is adapted to engage the cladding panel along the panel attachment portion and at no other location, wherein the upper upward projection is adapted to engage the second mounting slot in the first position such that the undercut clip (UCC1, UCC2) is in an upward orientation, wherein the lower upward projection is adapted to engage the first mounting slot in the second position such that the undercut clip is in a downward orientation, wherein the undercut clip is configured to be used interchangeably in either the first position or the second position, wherein the undercut clip is configured to permit vertical adjustment of the cladding panel, wherein the mounting surface includes a planar and vertical portion, wherein the undercut clip (UCC1, UCC2) has a mounting aperture in the panel attachment portion, and serrations formed in the panel attachment portion proximate the mounting aperture, wherein the undercut clip anchor system further comprises a nut bar washer having serrations for selectively engaging the serrations formed in the panel attachment portion of the undercut clip (UCC1, UCC2). a horizontal rail (H3, H3.1, H4) having a mounting surface for mounting to the structure, an upper upward projection spaced a first distance from the mounting surface, and a lower upward projection spaced a second distance from the mounting su rface, characterised in that the second distance is greater than the first distance; and an undercut clip (UCC1, UCC2) having a substantially planar panel attachment portion, a first mounting wall portion, a second mounting wall portion, a first bridge portion connecting one end of the panel attachment portion and a first end of the first mounting wall portion, a second bridge portion connecting a second end of the first mounting wall portion and one end of the second mounting wall portion, a first mounting slot formed between the panel attachment portion and the first mounting wall portion, and a second mounting slot formed between the first mounting wall portion and the second mounting wall portion; wherein the undercut clip (UCC1, UCC2) is adapted to be selectively mounted to the horizontal rail (H3, H3.1, H4) in one of a first position in which the upper upward projection is located in the second mounting slot, and a second position in which the lower upward projection is located in the first mounting slot, for anchoring a cladding panel, and wherein the undercut clip (UCC1, UCC2) is adapted to engage the cladding panel along the panel attachment portion and at no other location, wherein the upper upward projection is adapted to engage the second mounting slot in the first position such that the undercut clip (UCC1, UCC2) is in an upward orientation, wherein the lower upward projection is adapted to engage the first mounting slot in the second position such that the undercut clip is in a downward orientation, wherein the undercut clip is configured to be used interchangeably in either the first position or the second position, wherein the undercut clip is configured to permit vertical adjustment of the cladding panel, wherein the mounting surface includes a planar and vertical portion, wherein the undercut clip (UCC1, UCC2) has a mounting aperture in the panel attachment portion, and serrations formed in the panel attachment portion proximate the mounting aperture, wherein the undercut clip anchor system further comprises a nut bar washer having serrations for selectively engaging the serrations formed in the panel attachment portion of the undercut clip (UCC1, UCC2).