"If people in education did not feel they could make a difference to the lives of pupils in situations such as these, they should not be in the job," he told The TES.
Mr Wood, 46, who is currently acting executive director of education in Lambeth, south London, will arrive early in the new year to take up the post.
Liz Reid, the borough's education director, who has resigned, leaves today and in the meantime, Graham Badman, chief education officer at Oxfordshire County Council, will be acting director of education.
Mr Wood, whose appointment was overseen by the Department for Education and Employment, acknowledged the scale of the challenges he is facing.
But he said he planned to seek help from more successful neighbouring authorities - and if necessary the private sector - in addressing Hackney's problems.
Mr Wood applied for the permanent postion in Lambeth in the summer, but lost out to Michael Peters, York's director of education.
He should certainly be familiar with the challenges facing inner-city schools. He was at school in neighbouring Tower Hamlets, before spending eight years teaching in Brent in north London and the old Inner London Education Authority.
Having moved into local government in 1990 with Southwark council, Mr Wood joined Lambeth in 1997 as assistant director of education.
He became acting executive director of education in March, when former incumbent Heather du Quesnay was asked to stand in for departing chief executive Heather Rabbatts.
Opinion in Lambeth was divided on Mr Wood's reign. Some headteachers questioned his effectiveness in office. But Barbara Williams, principal of Norwood girls' school said: "Mr Wood is held in high regard by many of us here. He did a very good job of keeping the LEA on track.
"He is quite tough, but also a good listener. Hackney's gain is very much Lambeth's loss."