Dr Kiat W. Tan became Director of the Gardens in 1988. Guided by the vision of transforming the Gardens into a vibrant centre of active recreation, education, conservation and research, he laid out the master plan for the Singapore Botanic Gardens, a plan that has guided the development of many new physical features of the Gardens until today.

Over the past two decades, under the directorship of Dr Kiat W. Tan (1988–1996), Dr Chin See Chung (1996–2010), Dr Nigel Taylor (2011 – 2019) and Dr Tan Puay Yok (2019 to present), the Gardens has seen numerous improvements and special features added. These include the National Orchid Garden, Symphony lake and stage, the Visitor Centre complex at Nassim Gate, Ginger Garden, the 17-hectare Bukit Timah Core, Evolution Garden, Botany Centre, Jacob Ballas Children’s Garden, Healing Garden, Learning Forest, OCBC Arboretum and Seedbank, Centre for Ethnobotany and Botanical Art Gallery, among others. From October 2011 the northern end of the Gardens has been served by a train station (Circle and Downtown Line).

The Gardens has been inscribed as a UNESCO World Heritage Site in 2015. The Gardens is the first and only tropical botanic garden on the UNESCO’s World Heritage List. It is the first in Asia and the third botanic gardens inscribed in the world following Orto botanico di Padova and the Royal Botanic Gardens, Kew.

Despite the continuous improvements and developments, the Gardens still remains faithful to its roots and heritage. Lawrence Niven’s original layout of the Gardens still defines the Tanglin Core area, and historical buildings such as Burkill Hall (built in 1866–68), Ridley Hall (built in 1882),  E J H Corner House (built in 1910) and Holttum Hall (built in1921), have been conserved to remain true to their original condition. The Gardens has also seen a renewed focus on scientific research, and aims to become the leading international botanical institution for tropical botany and plant conservation in SE Asia.