The opening session focused on London and Paris. With metropolitan populations of 13.6 million and 12 million respectively, they are the largest conurbations in Europe and dominate their national economies. Both cities are ringed by major terminal stations and have well-developed metro networks, but this is where the similarities end.

While Paris has steadily-expanded its high-capacity RER network, which now comprises five lines totalling 587km, London only has one cross-city line - Thameslink. But as we report this month, the original Thameslink 2000 project to achieve metro-style frequencies in central London will not be completed until 2018 because of funding and planning delays.

However, Crossrail, London's second cross-city line, is making much better progress, as Mr Terry Morgan, Crossrail's managing director, told delegates: "We have been going for five years, and have another four to go and we are on time. We have completed three-quarters of the tunnelling and are mobilising to install the railway. We have 45 worksites and trying to ensure London doesn't go into gridlock is a major challenge."

London's population is expected to increase by 1 million within the next 10 years, so Crossrail will open just in time as Morgan explains. "Crossrail will allow an extra 1.5 million people to travel into London and gives the city a 10% increase in rail capacity, but I'm sure we will need to build a new north-south line. We have been protecting the route for Crossrail 2 - it's not a question of if but when."

While London may lag behind Paris in the development of high-capacity cross-city lines, it is ahead of its French counterpart in developing an outer ring to connect the inner suburbs. London's Overground network, which has been formed by upgrading existing lines and reopening disused sections of railway to form a cohesive network circling the city, has proved so popular that trains are having to be lengthened to cope with demand.

Mr Pierre Mongin, chairman and CEO of Paris Transport Authority (RATP), is all too aware of the need to improve suburb-to-suburb transport. "For the 6 million people in central Paris, the service is very good, but for people outside the centre it is a very different story," Mongin told delegates. Paris has a two-phase approach to address the issue. Light rail lines are steadily being opened to create an inner ring connecting the extremities of the metro.

By contrast, despite the success of the Croydon Tramlink LRT network in south London, schemes to build more light rail lines in the British capital have not materialised as the promoters have failed to make the case for light rail in the face of considerable political and public opposition.

The second phase in Paris is much more ambitious than the first and anything planned in London. The Grand Paris scheme involves extending Line 14 of the metro, and building four new circular lines totalling 193km, which will effectively double the size of the existing metro. The French government has committed an annual budget of €500m. A major element of Grand Paris will be the commercial development of land around half of the planned 72 stations, something which London has failed to capitalise on so far.

Both cities enjoy very high levels of capital funding. Mongin says RATP was able to invest €1.5bn from its own resources last year and cut its long-term debt by €150m. The government has also created a dedicated tax outside the state budget which Mongin says "provides a regular and safe source of financing."

Mr Mike Brown, managing director of Transport for London, says London Underground made a small operating profit in 2012-13 and expects a larger surplus in 2013-14 which will provide funding for investment. "The best way to persuade government to get funding is to deliver value, be on time and within budget," Brown says. "Getting a couple of successes under your belt makes a massive difference in obtaining investment from the government and private sector."

Both operators share the view that the biggest challenge is to get politicians to support long-term projects. "The short-term view is the biggest enemy of funding rail projects," says Mongin.

While London and Paris are doing a lot to provide high-quality public transport for their cities, the world is changing. An ageing population will place greater demands on operators, while rapid developments in technology are both an opportunity and a challenge. The two metros are moving to full automation which Mongin says delivers a 20% increase in capacity compared with manual operation. They are also getting to grips with the information age. For example, RATP issued its staff with smart phones last year to provide them with the same level of information as the passengers already enjoy.

A long-term vision, determination to succeed, and willingness to accept new ideas are qualities shared by both operators, which should stand them in good stead for the future.