Autoject® Micro is a pre-filled auto-injector designed to meet the demand for compact, discreet self-injections. Our design team deconstructed the traditional auto-injector and reengineered the drive mechanism to enable a smaller ergonomic device. The result offers the end user convenience and portability whilst offering pharmaceutical partners a more sustainable device, as cold storage and logistics costs are lowered. The Autoject® Micros patented drive mechanism enables true auto-injection, where the needle is inserted and medication is delivered automatically. Our design team worked closely with our human factors experts and identified the need for good visibility and clear audible and visual feedback so patients are reassured that their medication has been delivered and incorporated these needs into the compact design. A further requirement was the prevention of sharps injuries which was incorporated to reduce patient anxiety and the risk of needle stick injury. The design framework allows a choice of activation methods enabling the production of an optimal device to enable better medication adherence.