thumb|The former college buildings in 2008
La Sainte Union (LSU) in Southampton was a teacher training college. It was owned and run by the La Sainte Union des Sacrés Coeurs order of nuns, and this Catholic background was reflected in the student makeup.
In addition to teacher training, LSU also provided first-degree courses in the Humanities, particularly history (notably American and Soviet), art, English and foreign languages (B.A. Combined Studies, B.A. Modern Foreign Languages & European Studies, Theology). Although the education was provided by independent lecturers and professors the courses were overseen by the University of Southampton, and degrees, both ordinary and honours, were awarded by the university. Towards the end of its time LSU also started moving into medical training.
In April 1997 the Teacher Training Agency withdrew accreditation for the college's teacher training courses following the college's failure to pass an important academic validation inspection, and LSU closed. Bishop of Portsmouth Anthony Emery was quoted as saying "The full story cannot be told at the present time". At that time the college employed 315 staff and had over 2,000 students.