This chapter reviews progress in developing automated image-based systems for identifying crop insect pests. It identifies the challenges in distinguishing insect pests in field conditions and ways they can be addressed. The chapter outlines key steps in image-based identification (image capture, processing, segmentation, feature extraction and classification) and the growing use of artificial intelligence to increase accuracy and reliability. It also provides examples of commercially-available systems and assesses future developments. The chapter is aimed at practitioners and scientists new to the topic and as a useful reference on the pros and cons of different monitoring strategies for those already in the field.