Willie commenced his legal practice in 2016 as a pupil at Messrs Shukor Baljit & Partners, Kuala Lumpur. During his pupillage, Willie was guided by the Managing Partner of the firm, Datuk Baljit Singh Sidhu, a renowned criminal lawyer. As a pupil, Willie assisted the criminal defence team in many cases, from minor petty offences to serious offences with capital punishments.
After completion of his pupillage, Willie then joined Messrs Raslan Loong, Shen & Eow as a legal associate and headed the litigation department of the main office. At Messrs Raslan Loong, Shen & Eow, Willie worked closely with his mentor and the Managing Partner, Mr Loong Caesar. Mr Loong is a senior legal practitioner who co-founded Hishammuddin Loong (which is now known as Lee Hishammuddin Allen & Gledhill). Willie was involved in a variety of cases, including employment disputes, breach of contract, tort of conspiracy, insurance, debt recovery and etc.
Upon his return to Penang, Willie then founded Messrs Willie Ong & Co. Since Willie Ong & Co's inception, Willie has distinguished himself as a prominent and notable attorney. Just to name a few, together with the Penang Island City Council (MBPP), Willie executed the very first Warrant of Attachment in Penang, making history and as a deterrant to errant defaulters at stratified properties. Complex issues at high rise buildings and other housing accomodations such as illegal hotels and homestays have also been dealt with extensively by Willie. Willie gives talks frequently at webinars and forums particularly those concerning Strata Management. Willie is also no stranger to press coverage and local newspapers reports as well as legal precedents.
Willie is more than a lawyer. He is a debater, public speaker and social activist. He was once a member and the Speaker for the Penang Youth Parliament. Eloquent in 6 languages and dialects, he is no stranger to the local governmental as well as non-governmental activities and engagements. Contributing back to the society, Willie occassionally does pro bono works and public interest litigation. Willie is the Treasurer for the Penang Youth Committee (JBPP) for the Pengkalan Kota Constituency (N27) and he is also a lawyer registered with the National Legal Aid Foundation.