Pat Clark, Katy Blackler's head, is in her second headship. She moved to Avondale Park primary six years ago from The Peterborough primary school in Hammersmith and Fulham, south-west London, where she had been head for eight years.
"The head and deputy head relationship is one of the critical components of an improving school. It's like a marriage: people need to see the two people at the helm leading together and presenting a united front.
"This does not mean to say you cannot disagree. It's a bonus if you feel you can genuinely learn from each other and it's an even greater bonus if you become friends as well, which is what has happened with Katy and I.
"I've been very lucky to work with four excellent deputies. They are much closer to what's happening on the grund and they have the knowledge base and skills to develop teachers. They set the tone by pace-setting and then coaching.
"I value Katy's opinions more than those of any of my outside colleagues. We are not defensive with each other and she knows the context. She is very respectful of colleagues, but she always holds people to account.
"I have full confidence in leaving the school in her hands and I think this has been good for developing her confidence. In her eyes, I am more outgoing and confident. We are both reflective but she would employ the sloth factor more than I do and she helps me to put the brakes on. We both see ourselves as learners."
Professor Kate Myers, the interviewer, is director of the professional development unit at Keele University