Parallel to the formation of orthodox consumption function, there were alternative approaches to aggregate consumption originating from non-mainstream authors and schools of thought. These approaches criticised the basic assumptions and the underlying methodological framework of mainstream consumption functions. The present chapter will start with a discussion of their views, focusing mainly on the work of James Tobin whose work represents the standard Keynesian approach (sometimes labelled as ‘Old Keynesian’). It will proceed with a presentation of Kalecki and Kaleckian-based approaches, and with the views on consumption developed by Kaldor and Pasinetti. Finally, it will outline the broad common elements concerning aggregate consumption found in the contemporary Post Keynesian school.