Adrian Tan Gim Hai (4 February 1966 – 8 July 2023) was a Singaporean lawyer and author. Known for writing the Teenage Textbook series of books in the 1980s, he was the 27th president of the Law Society of Singapore and a partner at TSMP Law Corporation.^[1]

Tan was born in Singapore to an ethnic Chinese family of Hainanese descent. His parents were both teachers, and he grew up in a Housing Development Board (HDB) flat.^[2]

As a child, Tan attended the Anglo-Chinese School and Hwa Chong Junior College. Tan was later conscripted into the army as a writer for Pioneer, the MINDEF magazine.^[3][4] After his A-levels, he was offered a teaching scholarship to study English at the University of East Anglia. He turned down the scholarship to study law at the National University of Singapore (NUS).^[2] While in university, Tan represented NUS as a debater in international competitions and televised debates in Singapore.^[5] He later completed a second, joint-honours degree in computer science and psychology from the Open University in 2004, while working as a lawyer.^[6]

While an undergraduate law student at NUS, Tan wrote the novels The Teenage Textbook (1988) and The Teenage Workbook (1989), which became bestsellers that sold over 50,000 copies.^[7][8] The Teenage Textbook was also made into a stage play by The Necessary Stage in 1997;^[9] a film in 1998, which topped the box office in Singapore for four weeks;^[10] a 2017 musical titled The Teenage Textbook Musical;^[11] and a 2021 TV series on Channel 5.^[12] In 2015, The Teenage Textbook was listed by The Business Times as one of the top 10 English Singapore books from 1965 to 2015.^[13] Tan also was a consultant for the Channel 5 television legal drama The Pupil.^[14] Tan was invited to a National Library Board festival but later boycotted it over the board's decision to withdraw from its libraries children's books that depicted same-sex families.^[15]

After graduating from NUS with a Bachelor of Laws degree, Tan began his legal career in 1991 at Drew and Napier, a large Singaporean firm. He initially practiced conveyancing law, but switched over to litigation thereafter, where he worked under Davinder Singh.^[2][16] In 1999, Tan left Drew for a two-year stint as general counsel of a technology firm, following which he returned to Drew.^[16] Eventually, after 22 years at Drew, Tan left to work for Stamford Law (now Morgan Lewis Stamford) in 2013. In 2018, Tan resigned from Stamford to work at TSMP Law.^[2][17] Tan practiced litigation, and specialised in intellectual property, information technology, real estate, and shareholder oppression disputes.^[18] He was also the honorary counsel of the Singapore Association of the Visually Handicapped, where he advocated for voting rights for the blind.^[19][20] He was also a member of the boards of the Law Society Pro Bono Services,^[21] Maxwell Chambers,^[22] and Arts House Limited,^[23] and was a member of the Speak Good English Movement committee.^[24]

From 2013 to 2021, Tan was a member of the Law Society Council, serving as treasurer in 2016 and vice president in 2017.^[25][26][27] In 2022, he was appointed president.^[2] As president of the law society, he was known for his public outreach on legal issues,^[28] such as the HDB's ban on cats,^[29] the 2022 bar exam cheating scandal,^[2] and Richard Branson's comments on the death penalty in Singapore.^[30] Tan gave his only Opening of the Legal Year speech as Law Society president in 2023, where he addressed attrition rates in the legal profession.^[31]

Tan was married without any children.^[32] He was diagnosed with cancer in March 2022,^[33] and died on 8 July 2023, at age 57.^[34] At a memorial service celebrating his life, Tan was said to be someone who "had very little ego", was a champion of the legal profession and who "cared for the less fortunate."^[35]

After his death, a collection of essays by Tan on the issues he cared about and commented on, was published in a book entitled, "If I were King of Singapore."^[36]

• Wee Shuo Woon v HT S.R.L. [2017] SGCA 23^[37]
• Turf Club Auto Emporium Pte Ltd v Yeo Boong Hua [2018] SGCA 44^[38]
• Singsung Pte Ltd v LG 26 Electronics Pte Ltd (trading as L S Electrical Trading) [2016] SGCA 33^[39]
• Y.E.S. F&B Group Pte Ltd v Soup Restaurant Singapore Pte Ltd (formerly known as Soup Restaurant (Causeway Point) Pte Ltd) [2015] SGCA 55^[40]
• Acted as counsel in proceedings concerning Gilstead Court,^[41] Thomson View,^[17] and Shunfu Ville^[42] collective sales.

• "Dear Adam, Help!" (1988, Hotspot Books), ISBN 981-3002-35-2
• The Teenage Textbook (1988, Hotspot Books), ISBN 981-3002-21-2
• The Teenage Workbook (1989, Hotspot Books), ISBN 981-3002-28-X
• "What Practice Has Taught Me" Archived 8 July 2023 at the Wayback Machine in The Practice Of Law (2011, LexisNexis), ISBN 978-981-4753-48-7