Although the majority of the world’s laying hens are still housed in conventional (‘battery’) cages, public concern for the welfare of laying hens is rapidly changing the methods by which eggs are being produced and marketed in many regions of the world. However, alternative housing systems have their own costs and associated welfare problems, as well as benefits. There are also various welfare concerns for laying hens which are not based solely on how adult laying hens are housed. In this chapter we provide an overview of the current state of knowledge on the major welfare issues for laying hens, including the welfare trade-offs involved with different housing systems, the behavioural requirements of laying hens, the issue of injurious pecking and skeletal health concerns. We also identify new and emerging issues that are directing future research in the area.