Posters, stickers and hanging mobiles asking diners to return their trays can be seen at five Kopitiam outlets.
Look out for them at Plaza Singapura, Hougang Mall, Tan Tock Seng Hospital, Changi Airport Terminal 3 and Bukit Panjang Plaza.
Please do your part.
Send in photos and details of the worst examples of dirty tables and uncleared trays to ST's interactive portal Stomp: e-mail 75557@stomp.com.sg or MMS 75557.