After graduating, Dr. De Silva worked at Conservation International for over eight years, starting as a Senior Advisor for Asia-Pacific Conservation Priorities in 2004. In this role, she supervised staff and partners, led capacity building, supported fundraising, provided training, assisted in project development, and developed memoranda of understanding and joint policy statements. She was promoted to Director of Conservation Priorities and Outreach in 2011, where she led the development of priority-setting frameworks. Specifically, she helped develop innovative methods for mapping biodiversity and ecosystem services, where she collaborated with stakeholders worldwide. Moreover, De Silva led the priority setting of multi-institutional Critical Ecosystem Partnership Fund projects, including the African Great Lakes. During her eight years with the organization, she traveled to the Philippines, Papua New Guinea, China, Australia, Botswana, New Caledonia, and Japan, among many other countries, to advance conservation goals. In each place, she saw the diversity of leadership within various organizations.

Upon leaving Conservation International in 2012, Dr. De Silva joined George Washington University in 2014 as a Fellow while she was a doctoral student, where she supported teachers and staff at D.C. Public Schools via community partnerships, grant writing for sustainability, and professional development. She became Strategic Advisor in 2015 while still a Fellow. As a Strategic Advisor, she contributed to the Office of Sustainability, the Honey W. Nashman Center for Civic Engagement and Public Service, and Sustainable George Washington. Some of the projects she worked on included university-wide strategies for sustainability, student engagement, data analysis, and budget management. In this role, Dr. De Silva also mentored students who were considering service projects related to social and environmental justice.

In 2017, she founded Mayla: Community for Nature, which celebrates and supports the diversity of people who protect nature through storytelling, consulting, and mentoring. She oversees workshops, mentoring, and organization programming. Dr. De Silva currently serves in three additional roles outside of Mayla. Dr. De Silva started as a consultant for Bernuth and Williamson in 2019, where she focused on projects related to inclusion and the environment for clients, including the World Wildlife Fund, Trout Unlimited, and VentureWell. She is also a Professorial Lecturer of Sustainability at George Washington University as of 2020, where she teaches a capstone seminar entitled "Community Engaged Research to Promote Environmental Justice." This course uses qualitative research methods and environmental justice principles to emphasize the importance of intersectionality and noticing (listening, paying attention, and observing). Part of the curriculum she developed has students engage in a research project on environmental justice topics of importance in D.C. or home places. In addition, Dr. De Silva works with the American Bird Conservancy as their Chief Diversity Officer, where she celebrates the diversity of birds and those who cherish and conserve them. Among her responsibilities are recruiting new staff, creating partnerships to promote environmental education, and using storytelling to include more diverse perspectives.