Peel 3 oranges, remove pith and cut into segments.
Remove rind from bacon, fry gently and cut into 2.5 (1-inch) squares.
Remove skin and membrane from chicken and cut into 2.5 cm (1-inch) cubes.
Thread 4 skewers alternatively with orange segments, chicken, cooked mushroom caps and bacon.
Squeeze juice from remaining orange and combine with melted butter.
Brush kebabs and grill over hot coals, turning once or twice until lightly browned on all sides.