This year marks the 50th Anniversary of diplomatic relations between Singapore and Indonesia, a significant milestone for both countries. To commemorate and celebrate the close bilateral ties of both countries, Singapore Post and Pos Indonesia have jointly released this joint stamp issue featuring corals found in both countries. The coral reef theme was chosen to signify the diversity in our relationship and how Coral reefs form part of an underwater ecosystem that sustains a wide variety of marine life. From the perspective of biodiversity, coral reefs are also known as the tropical rainforest of the sea. Around a million species of marine life inhabit this ecosystem and yet it is very vulnerable to environmental changes. One of the main benefits of coral reefs is in being a source of food as they provide a place where fishes can breed. They serve we are linked by a common marine landscape as a coastal abrasion retarder against strong waves.