Romelu Lukaku, on loan from Chelsea, hoisted Albion to third in the Premier League with the winner on his first start for the club.
The Belgian striker, for whom Chelsea paid Anderlecht a £13m fee which could rise to £18m with add-ons, struck after 71 minutes with a low, left-footed shot from 18 yards.
He had been promoted to the starting line-up in interesting circumstances. Albion's Shane Long said he wouldn't celebrate if he scored against his old club. Fair enough thought the manager, Steve Clarke, and dropped him in Lukaku's favour. If fairness, Long still had a significant part to play. On as substitute after 65 minutes, he set up the goal with a headed knock down.
Lukaku was always busy and willing, but for a long time Albion too often tried to thread eye-of-the-needle balls through to him, which complicated his task and simplified that of the Reading defence. In the first half, therefore, it was to left to James Morrison to provide the threat to Alex McCarthy's goal, first with a skimming shot, turned behind, then and a scuffed effort at close range. When the Belgian had his first inviting chance, after 44 minutes, his heavy first touch in front of goal allowed Kaspars Gorkss to clear behind. From the consequent corner, taken by Chris Brunt on the right, Jonas Olsson climbed highest and headed against the top of the far post.
Reading were toothless throughout, their only strike of consequence a bicycle kick from Gareth McCleary, comfortably saved.
Morrison tested McCarthy for a second time with a thumping drive from the edge of the D that had the goalkeeper sprawling to his right, and McCarthy came to Reading's rescue again when he advanced from his line to thwart Lukaku, who had dispossessed Chris Gunter to break clear.
When it finally came, the goal was no more than Albion's superiority deserved. It saw Long head down a cross from Graham Dorrans to Lukaku who, standing on the 18 yards line, dispatched a low drive past McCarthy's reaching left hand.
The Baggies are up to the heady heights of third in the table. Boing boing as they say in these parts..