From 1999 to 2001, María Arango worked with Giancarlo Mazzanti, where she participated in several public engagements and competitions, including the 40 km Fucha River Linear Park and the Tercer Milenio downtown park in Bogotá.
In 2001, María joined ONG&ONG Pte. Ltd., where she initially took charge of designing a variety of projects, ranging from public works and private residential developments to master planning competitions. Notable projects during this time include the conceptualization and design of the Nicoll Highway MRT Station and The Summit, a 36-storey apartment building in Jakarta, Indonesia.
During her 20-year tenure at ONG&ONG, María, alongside Diego Molina, led a design studio specializing exclusively in high-end residential projects and the restoration of conservation and heritage buildings. Many of these projects received awards and recognition both locally and internationally.
In August 2021, María, together with Dr. Goh Chong Chia and Mr. Diego Molina, co-founded ArMo Design Studio Pte. Ltd., a boutique design consultancy firm. ArMo adopts a holistic design approach that encompasses space planning, architectural design, and interior design for residential developments in Singapore and the region.
