The renowned International Semiconductor Laser Conference (ISLC) is dedicated to latest developments in semiconductor lasers, amplifiers and LEDs. It has represented excellence from all global regions and all areas of semiconductor laser research for over 50 years, and now returns to Germany after a 19 year gap. ISLC 2021 and associated exhibition are organized by the Ferdinand-Braun-Institut, Berlin and supported by IEEE Photonics Society as technical sponsor. Abstract deadline is 14 May 2021.