The MINI comes in three models: the MINI One, the MINI Cooper, and (from 2002 onwards) the supercharged MINI Cooper S. There is also a diesel engine variant called the MINI One/D. In Portugal, the MINI One is powered by a 1.4 l version of the Tritec engine but all other gasoline powered MINIs use the 1.6 l version. Since 2005, a soft-top convertible option has been available across the entire range.

There are numerous styling and badging differences between the three models, perhaps the most obvious are that the Cooper S has a distinctive air duct cut into the bonnet (which improves airflow over the top mounted intercooler), it also has twin exhausts. The (non-S) Cooper has more chrome parts than the MINI One and has a single exhaust. The MINI One/D has no visible exhaust pipes at all.

In some markets, such as Australia and the US, only the MINI Cooper and Cooper S are sold because the MINI One's engine was considered to deliver insufficient power to run an air conditioner - a necessary feature in those climates. Almost fifty percent of all MINIs sold in Australia and about seventy percent of those sold in the US are the top-of-the-range Cooper S model.

The MINI One, Cooper and Cooper S use a Brazilian-built Tritec engine while the MINI One/D uses a Toyota-built diesel engine.

While the modern MINI uses none of the engineering of the original Mini, it does capture much of the spirit of the classic car. Like the original, it uses a transversely-mounted four-cylinder engine driving the front wheels. All four wheels are pushed to the corners of the body which is a 'two-box' or "hot hatch" design. The styling of the car, like that of the Volkswagen New Beetle, is deliberately reminiscent of the original with contrasting roof colours, optional bonnet stripes and rally lights and with black trim around the wheel arches and rocker panels that mimic the wide wheel flares found on many classic Minis.

Dr. Alex Moulton, designer of the original classic Mini's suspension is reported to have said about the new MINI "It’s enormous – the original Mini was the best packaged car of all time – this is an example of how not to do it... it’s huge on the outside and weighs the same as an Austin Maxi. The crash protection has been taken too far. I mean, what do you want, an armoured car? It is an irrelevance in so far as it has no part in the Mini story."

The MINI One and MINI Cooper are available with a continuously variable transmission or with a conventional five-speed manual transmission. The Cooper S comes with a six-speed Getrag manual or (from the 2005 model year onwards) a fully automatic transmission with paddle shifters.

Technical innovations include an electrically-driven power steering system which avoids robbing power from the engine when accelerating out of corners, and equal length driveshafts to eliminate torque steer. The MINI has a 'drive by wire' electronic throttle, electronic brakeforce distribution, and traction control to improve control and handling in adverse conditions.

Adding a supercharger to the Cooper S model required that the battery be relocated into the rear of the car - leaving no room for a spare tyre. Hence this model comes with run flat tyres as standard.

At the 'Salon International de l'Auto' (Geneva Motor Show) in 2004, MINI introduced a cabriolet (convertible) model to be released in the 2005 model year.

The car is available in One, Cooper and Cooper S versions.

The convertible roof is fully automatic - an unusual feature in such a small car - and can be opened partially to act as a sunroof whilst the car is driving at speed. The convertible model forsakes the rear hatch of the hardtop MINI - replacing it with a 'tailgate' design modelled closely after the classic Mini - and adds two small power windows for the rear seat passengers. The roof is made from a heavy cloth with many layers of insulation, the rear window is of glass and has a heater/defroster but no washer or wiper.

Many owners criticise the poor rear visibility in the convertible. With the roof up the wide areas of cloth down the sides of the car block visibility to the rear quarters and the lack of washer/wiper on the small rear window - combined with the tendancy of all MINIs to accumulate dirt on the back end - effectively eliminates all rear visibility. Even with the roof down, the large roll-protection bars above the back seats and the bunched up cloth of the folded roof block a significant fraction of rearward visibility. In an attempt to counter this problem when reversing the car, the MINI convertible comes with rear-mounted proximity sensors as standard equipment (these are also available as an option on the hardtop MINI).

Whilst the car has been criticized for its poor space-efficiency compared with the original Mini (despite its significantly larger size), its faithfulness to the original's razor sharp handling characteristics and its unique styling has seen the MINI quickly become a sales success in Europe and (from 2002) in the US.

BMW has received a significant backlog of orders throughout the life of the car and the Cowley factory is working at its full capacity of around 100,000 cars per year; all of this with little conventional advertising.

The car has featured in many movies, most notable of which is the 2003 remake of The Italian Job, but see also: List of movies in which Mini cars are featured.

The new MINI has achieved cult status worldwide with many owners being approached by complete strangers who wish to take a closer look at their MINI, or to recall their own classic Mini tales. As with the classic Mini, the new MINI has a widespread club and enthusiast following and strong after-market support for performance upgrades and styling enhancements. Such community support keeps the brand highly valued and shows BMW's decision to relaunch the MINI as a successful business strategy.

The MINI Cooper/Cooper S won the North American Car of the Year award for 2003.