CL seedings for the group stage see holders Barcelona among the front-runners, while Borussia Dortmund promises a 'group of death' from its lowly place in Pot 4.
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How it works
The 32 qualifiers have been divided into four pots based on the UEFA coefficients, which are in turn decided by a mixture of the team's own performance in Europe over the past five seasons, as well as the strength of their country's league.
The Champions League group stage comprises eight pools of four teams: consequently, a team from each pot is drawn and placed into one of the eight groups available. This is done by pot and not "one at a time": that is to say, all the teams from pot one will be placed into a group, and then pot two, and so on down to the fourth and final pot.
There are some restrictions, though. Teams from the same national association cannot be drawn together, and even prior to that there will be two 'sets' of groups decided for the purpose of television rights. For example, the four teams from Spain cannot all be drawn in the same set.
Pots
The Champions League Group Stage pots for 2011-12 are as follows:
| Pot 1 | Pot 2 |
 Manchester United |  AC Milan |
 Barcelona |  Olympique Lyonnais |
| Chelsea |  Shakhtar Donetsk |
 Bayern Munich | Valencia |
| Arsenal |  Benfica |
| Real Madrid | Villarreal |
| Porto |  CSKA Moscow |
| Inter | Marseille |
| Pot 3 | Pot 4 |
| Zenit St Petersburg | Borussia Dortmund |
 Ajax | Napoli |
| Bayer Leverkusen |  Dinamo Zagreb |
 Olympiakos |  APOEL Nicosia |
| Manchester City |  Trabzonspor* |
| Lille |  RKC Genk |
 FC Basel |  Viktoria Plzen |
 BATE Borisov |  Otelul Galati |
Source: Bert Kassies - http://kassiesa.home.xs4all.nl/bert/uefa/
*Late replacement for Fenerbahce, which was removed from the competition on Aug. 24
*Late replacement for Fenerbahce, which was removed from the competition on Aug. 24
What to look out for
- The Group of Death: Just how hard can the Champions League be? Consider the strength of a group such as the following: Barcelona, AC Milan, Manchester City, and Borussia Dortmund ... Or how about Manchester United, Benfica, Zenit and Napoli? Chelsea, Lyon, Bayer Leverkusen and Basel, too, could be considered among the toughest of the lot - but so also could Real Madrid, CSKA Moscow, Ajax, and APOEL.
- Old Rivalries: Teams from the same country can't meet at this stage, but if familiarity breeds contempt there's still scope for some serious contests. Ajax, the old campaigners of Europe, has faced Real Madrid many times (including last season) and will hope to avoid a fifth meeting. Meanwhile, Chelsea and Porto have a great history - and a very recent one, at that ...
- Recent Reunions: Real Madrid finally got one over on Lyon last season, but may well relish a rematch against its French opponents. Meanwhile, Arsenal may fancy its chances against a Shakhtar Donetsk side which edged it to second place in the last group stage. Finally, how about a meeting between AC Milan and Manchester United? Remember how their last battle ended up in the 2009-10 competition...
