The purpose of sensory systems is to drive behaviour.  Yet the bulk of our knowledge of sensory systems comes from experiments on anaesthetised animals where the motor systems are disengaged.  In the past, technical limitations made it difficult to study this topic in behaving animals but methodological advances are changing this.  The broad aim of our research is to investigate the neural basis of sensation in the behaving brain.  In this talk, I will focus on Sensory Adaptation (SA) – exemplified by the phenomenon that the response of neurons to repeated sensory stimuli of fixed strength decreases over time.  SA has classically been regarded as a fundamental aspect of how neurons respond to sensory signals.  However, our knowledge of it comes almost entirely from experiments on anaesthetised animals and it is controversial whether or not SA has much influence on neurons under awake, behaving conditions.  We tested whether SA occurs in awake, behaving mice in a new way, by combining in vivo electrophysiology from behaving mice with multi-camera imaging of the whiskers and machine vision. Our findings show that SA does occur in the whisker system of behaving mice and support the view that SA is indeed a fundamental aspect of sensation.