Balwant Singh Sidhu was called to the Malaysian Bar in 1983 and set up his own law firm in 1985. He has handled numerous cases in criminal law, civil and commercial law, land law, constitutional law and especially family law. He was admitted Ad hoc to the Supreme Court in Brunei To handle a family law case in 2002 and a corruption case in 2005. He was asked to give Legal opinions to family courts in England and Australia on Malaysian family law, and called to Melbourne as as expert witness. He has given talks on family law over the years, including at a Malaysian law conference and at seminars. He annotated the law reform ( marriage & divorce) act 1976 for Malayan law journal in 1995. He has written articles on family law for MLJ. A large number of family law cases that he has handled over 35 years are reported in Malayan law journal, including some leading cases. He is a member of the family law committee of the Malaysian bar council, and is a leading family law specialist.