The brain of all vertebrates contains a circadian clock, driving daily rhythms of behaviour, physiology and the neuroendocrine system. Systems as diverse as hibernation, seasonal reproduction and fattening cycles, daily activity and feeding cycles and sleep-wake rhythms are all driven via output from the circadian clock, entrained by light via specialised neural pathways. We are interested in how clocks time physiology and behaviour, and their relevance for normal physiology and disease. Our approach is primarily genetic, and we use as models transgenic mice – many now engineered locally using CRISPR-based technology. For our studies of seasonal timing mechanisms, we use sheep and for hibernation studies the Alaskan Arctic ground squirrel. Currently, we have 3 post-doctoral scientists in the laboratory, 3 technicians, 2 PhD students, and in collaborative programmes involving an additional 5 post-doctoral scientists.