1 Solid foundations
Cardiff have cut loose as an attacking force at times this season, but with 17 clean sheets prior to Tuesday night's match against Charlton, their success has largely been built around a solid defence. With David Marshall impressive in goal and Mark Hudson, the captain, a commanding and influential figure in the heart of central defence for much of the campaign (he has been sidelined with an ankle injury since the middle of last month), Malky Mackay's side have been obdurate opponents.
2 Team ethic
When every Championship manager was asked to name their best five players in the division, not one member of Mackay's squad polled enough votes to finish among the top six names, despite running away with the league. But as the goalscoring charts illustrate, it is all about the team rather than the individual at Cardiff. In the absence of a prolific striker – there is not one Cardiff player who has managed to get into double figures in the league this season – the goals have been shared around the side.
3 Mackay's leadership
As Cardiff have come up short at the play-off stage in the previous three seasons, a fair chunk of credit must go to Mackay for finally getting the club over the line. The Cardiff manager has had a decent budget to work with, both in terms of transfers funds and wages, but he has also had to deal with off-the-field distractions, including the fall-out from the colour change and speculation about the club being renamed. Amid everything, Mackay has been a calm head, keeping his players focused and diligently plotting the club's return to the top flight.
4 Leading from the front
The fact that Cardiff climbed to the Championship summit in November and have stayed there ever since is testament to the players' mental fortitude, especially when the club has picked up a reputation in previous seasons for choking when the pressure is on. Mackay has continually preached the importance of "monotonous consistency" and his players have taken that message on board, relentlessly grinding out victories, especially at home. There was a little wobble across February and March but never any real sign that Cardiff would collapse.
5 Financial backing
While Vincent Tan's decisions last June to change the shirt colour from blue to red and alter the club crest was hugely controversial, the Malaysian owner stayed true to his promise that he would pump money into the club if the radical rebranding exercise went ahead. Cardiff splurged more than £10m in the summer, making them the Championship's biggest net spenders, and Craig Bellamy joined on a free transfer. The financial gamble paid off and promotion means a PR disaster has been avoided.