In BBC2s Bafta- nominated series Protecting Our Children, unprecedented access took the viewer to the heart of the issues facing Britain’s social workers. But it also presented enormous challenges to the programme makers, as well as unusually at-risk contributors. So how did they do it, and what were the pitfalls along the way? Brian Woods, who has himself produced several award-winning films around vulnerable children, talks to the series producer Sacha Mirzoeff as well as contributor and social worker Ben Crang , and director of photography Petra Graf.