Melissa is Directorat Wah & Hua Pte Ltd, Director at ALBA W&H Smart City Pte Ltd,  and the Chairman at Waste Management and Recycling Association of Singapore (WMRAS). Melissa spearheads Wah & Hua Pte Ltd. and her life has revolved around the waste management and recycling industry for the past 20 years.

Being a passionate environmentalist, Melissa is the Chairman of the Waste Management and Recycling Association of Singapore (WMRAS) and has served for 3 consecutive terms. Melissa also chaired the Asia Pacific Waste and Environmental Alliance (APWEA) which was established to facilitate the transfer of knowledge and raise standards.