It was a well merited victory carved out by goals from Liam Ridgewell and James McFadden, but they had to survive a late challenge following an own goal from Scott Dann.
Birmingham certainly responded to the challenge to improve their flagging fortunes with a pleasing display of attacking football against a Sunderland side who never managed to really test the opposition.
Steve Bruce made his first return to St. Andrew's since his acrimonious departure two years ago. He was given a warm welcome by the home fans, but it did not turn out a happy return as Sunderland only came to life in the last 15 minutes.
There was no beachball on this occasion to assist them and at times they were all at sea against the hard running Birmingham outfit who had a point to prove.
Over all there was a significant improvement in Birmingham's performance and in particular from McFadden.
He had been asked to make a more positive contribution in the goalscoring stakes but the Scotland international could only produce a weak effort early on after being set up by Christian Benitez.
They later combined again but on this occasion McFadden was foiled by a good tackle from makeshift defender Kieran Richardson.
Boosted by this move Benitez moved in smartly to hammer in a goalbound shot only for Craig Gordon to make a smart save.
At this point very little had been seen of the Sunderland attack with the goalscoring Darren Bent unable to make any impact against the strong-tackling Roger Johnson.
In the 37th minute Phil Bardsley conceded a free-kick which Seb Larsson curled to the near post where Ridgewell deflected the ball past Gordon and into the net.
Birmingham appeared to have more determination about their play as Sunderland failed to ignite despite some good probing play from Andy Reid.
This was certainly demonstrated two minutes in the second half when the Blues increased their lead. Larsson's forward pass was knocked on by Cameron Jerome into the path of McFadden.
The Scot cleverly dragged the ball back onto the inside of Bardsley before slotting a low shot into the far corner of the net.
Sunderland made a triple substitution in the 68th minute sending on George McCartney, Fraizer Campbell and Bolo Zenden.
The changes had the desired effect as Sunderland pulled back a goal eight minutes from time.
Richardson's free-kick was headed on by Michael Turner and Dann, attempting to clear, turned the ball into his own net.