Christina Tracy Boxer-Cahill (born 25 March 1957) is a retired female middle distance athlete from England.

She represented Great Britain at three Olympic Games, in Moscow 1980, Los Angeles 1984 and Seoul 1988 and trained at Aldershot, Farnham & District AC.

She gained a BSc in Physical Education and Sport Science and a PGCE in PE & Biology at Loughborough University between 1979 and 1983.

On 6 July 1984, Boxer achieved her career best of 4:00.57 in the 1500 m at Gateshead, to break Christine Benning's five-year-old British record.

She ran her best ever time in the 3000 m, with 8:49.89 at the Crystal Palace and finished second in the 1500 m at the European Cup in Moscow, behind Raviliya Agletdinova of the Soviet Union.

Competing at her third Olympics in Seoul, South Korea, (under her then married name of Cahill), she finished 4th in the 1500 m final, with her best time for four years, 4:00.64.

Boxer continued to combine consultancy work with formal employment contracts and project management and has held honorary positions promoting sport and coaching.