Derby showed character to survive a tense finale and beat a well-organised Reading side to end a run of three straight defeats.
Goals from Tommy Smith and Marcus Tudgay put Derby into a 2-0 lead with seven minutes left, but a well struck free-kick from Nicky Shorey subjected the home team to a nerve jangling last few minutes.
Four minutes of stoppage-time only added to the tension and Reading twice went close before the final whistle brought relief to the majority of a 22,000 plus crowd.
It was a big win for Derby against a team that had conceded only one goal in their previous five matches.
The Royals were strong and solid in a decidedly scrappy first half, when the closest either side came to scoring was when Andy Hughes struck the Derby crossbar when attempting to put the ball out of play after Nicky Forster needed attention for a head injury.
The second half also suggested the game would end in stalemate until Derby brought on teenage midfielder Tom Huddlestone in place of skipper Ian Taylor.
The 17-year-old immediately injected some spark into Derby although it was Reading who almost went in front, butn David Kitson was foiled by an excellent save from Lee Camp.
Reading's Marcus Hahnemann did even better when he leapt to his right to tip over a 20-yard shot from Marco Reich that was heading for the net.
The corner led to the opening goal as Reich collected the ball just outside the penalty area on the left and delivered a teasing cross to the back post that Smith headed in from eight yards.
Derby now sensed victory and a second goal arrived seven minutes from the end with Smith this time the provider.
Shorey was caught in possession near the dead ball line and Smith set up Tudgay at the near post, and he drove a right-foot shot from the edge of the six-yard box into the roof of the net.
That should have been the end of the contest but Reading showed why they are rated as one of the top candidates for promotion.
When Michael Johnson was adjudged to have fouled Forster just outside the area, Shorey curled a left-foot shot over the wall and into the top left corner of Camp's goal.
Derby were now hanging on and a minute later another Shorey free-kick almost cracked in at Camp's right-hand post.
However, Mo Konjic marked his long awaited debut with some towering headers in injury-time and Johnson also made a vital interception as the Rams clung on to claim a vital victory.