The BMW WilliamsF1 Team experienced a season of mixed emotions. From the outset it was known that both drivers would be joining new teams in 2005, not the perfect foundation on which to build a world championship campaign.

Furthermore, the team, like its rivals, was caught out in Melbourne by the immediate, out-of-the-box, pace of the Ferrari, while its radical nose was (quietly) dropped later in the season.

As BAR and Renault chased after Ferrari, leaving WilliamsF1 in their wake, Ralf Schumacher missed six races following a horrendous accident at Indianapolis. A re-shuffle, which saw Sam Michael promoted and Patrick Head moved sideways, was immediately followed by a spate of disqualifications.

Thankfully it all turned out right in the end, with Ralf Schumacher taking a convincing second place in Japan, and Montoya scoring a fine win in Brazil, the team's first victory since Germany 2003.

Despite reports that BMW is unhappy with the lack of progress in 2004, BMW Motorsport director Mario Theissen is delighted with the way the team's revival, its demonstration of true fighting spirit.

Asked what gives him the confidence that the team will be more successful in 2005, Theissen replies: "Two factors in particular: Over the course of the 2004 season, we have been able to fight back and improve the car so much that we could take a second place and even a victory in the final rounds. This proves the substance and the strength of the team and underlines that it never lost its motivation.

"Factor two," he continues, "both we and WilliamsF1 have started to develop the car and engine for the 2005 season very early on. The development is making good progress, and I'm confident that our new package will enable us to make a major step forward."

So has it been a major achievement making it back to the front end of the grid? "This return to competitiveness was the result of a huge effort," he admits. "On the one hand we had to smoothly execute the regular racing business, on the other we were busy developing the 2005 car and engine. But due to the situation, we also had to find the time for a major improvement to our current package. This was a test our team never had to undergo in the past.

"WilliamsF1 has carried out two major changes to the aero package," he adds, "the new sidepods that were introduced at Magny-Cours, and then the return to a more conventional front from the Hungarian Grand Prix. Furthermore, there were further measures taken for every single race. I'm highly appreciative of this effort as it demonstrates the team's morale."

And what about the performance of the BMW P84 engine? "I was extremely happy with the P84," he replies. "We have made three steps to cope with the new challenge represented by the fact that the 2004 engine had to cover twice as many kilometres as its predecessor. At first it was all about building a reliable engine that was able to cover the required distance. Our next goal was to be able to deliver the maximum revs not only over a qualifying lap but over the entire race distance. From Barcelona, we were able to rev to nearly 19,000rpm during the race - even in the highest gear, something quite remarkable in Formula One. The third step was to focus on the performance development. With hindsight, I believe that the P84 has once again set the benchmark in Formula One when it comes to the sum of its characteristics, performance and reliability."

Looking ahead to the rule changes for 2005 and 2006, how does he assess the FIA's measures?