There has been much controversy over whether the claims of sociobiology and related schools of thought, including Evolutionary Psychology, if true, imply that we humans are significantly less free than has traditionally been thought. The defenders of these schools themselves often respond to this concern by claiming that it presupposes that they believe in genetic determinism, which they do not. Philosophers, such as Janet Radcliffe-Richards, respond by appealing to compatibilist accounts of free will. The thought is that whether or not our behaviour is caused by evolved mental mechanisms has no bearing on whether or not it is free. The present paper takes issue with this use of compatibilist arguments, and argues that they do not absolve sociobiology’s most prominent successor-theory, Evolutionary Psychology, from the charge of suggesting that we have less free will than we might have otherwise thought. Compatibilist accounts of free will distinguish between situations where we are free and ones where we are not, the latter including not just situations of external coercion, but also situations where there are internal obstacles such as compulsions, addictions or phobias. While not attempting to outline a full account of what it is to be free, this paper outlines one set of conditions which are sufficient for our freedom to be said to be restricted – conditions which obtain in situations of addiction, etc. A central pillar of Evolutionary Psychology is that the mind consists wholly or largely of modules whose operation is mandatory. The present paper argues that this implies internal obstacles to free will that are relevantly similar to addiction, self-deception, etc. Moreover, it is Evolutionary Psychology’s commitment to their version of the modularity thesis, and not any genetic determinism, that leads to this conclusion. Hence, the view that Evolutionary Psychology implies that we are less free than has traditionally been thought is not without foundation.