I've known Stef for all of his, nearly twenty, years of working in NATS and he stood head and shoulders, literally and metaphorically, out from the crowd throughout. His knowledge and expertise, alone, shone out in an organisation built from specialist talent. I saw these words recently; To grieve you have first to truly love someone. There's a lot of shared grief out there for Stef's passing. My thoughts are with you all at this incredibly sad time.