Every clinician experiences moments when 'they don't know what to do'. Modern medicine is increasingly complex and training has also become more complicated. The days of 'see one, do one, teach one' are over. Yet, both younger clinicians and senior practitioners describe uncertainty as one of the most challenging and stressful aspects of clinical work. If uncertainty is uncomfortable or threatening to individual practitioners, it also provides complex educational challenges. How can we learn to cope with uncertainty effectively ourselves? How can we teach others to understand and manage uncertainty?