Balance PointsBalance points are marks and notches that help align adjoining pattern pieces when constructing a garment.
Image 1In this image there are notch points in (1) the Bodice Back side seam and in (2) the shoulder front.
Image 2The side seam notch is a balance point that will line up with the dart in the Front Bodice piece. When the front and back are lined up at the side seam, you can see that the notch (balance point) in the back lines up with the dart on the front piece.
Image 3This must true whether you line them up from the armhole (image 2) or the waist (image 3).