What can I do about paint peeling off my ceiling?

I have paint peeling from two ceilings in my home and we want to paint them. What should I do?

Firstly do adhesion tests on any remaining paint to see if other areas on the ceiling have poor adhesion. If the area affected is extensive then remove all the existing paint back to the bare surface. Then apply one coat of British Paints Acrylic Sealer Undercoat and two coats of British Paints Ceiling. For peeling from fibrous or set plaster, follow same instructions, but apply one coat of British Paints PREP 4 in 1 (oil based), allow 48 hours to dry, and then 2 coats of British Paints Ceiling.