The London 2012 Olympic Games are over and the baton has been passed to Rio de Janeiro. The Brazilian city has four years to prepare for its Games, the first to be held in South America.
So what can Rio learn from London?
1. Be prepared
From gold medal-winning boxer Nicola Adams, who called the food in the athletes' village "incredible", to the International Olympic Committee (IOC), who have noted the plants and trees on the Park, Rio needs to complete the major projects to also nail the minor aspects. They are the ones which secure glowing reviews from athletes, spectators, officials, staff.
Brazil hosts the World Cup in 2014 and the Maracanã Stadium for that and the 2016 Games is not yet complete. The organising committee says progress is on track. But journalists from Brazil who have been in London say it is being monitored in the last-minute land of "instant gratification".
2. Sort out ticketing
It's the biggest bugbear of the Games. The furore focused on demand for the most popular events outstripping supply before London 2012 began. During the Olympics, the sight of empty seats at the so-called Greatest Show on Earth, when people wanted to watch sport, irked the most. The battle to buy any tickets released late online came a close second.
The IOC has promised to look at the issue. How it resolves the distribution of tickets to National Organising Committees and accredited ticketing agencies remains to be seen. But in London questions about it flowed throughout.
3. Harness volunteers
In London, they are the most praised aspect of the Games. They have directed people, cheered them up, worked so hard. No country in the world has cash to splash in the current economic climate. A free workforce of 70,000 volunteers in London delivered the Games across the line. And Rio would do well to replicate that with a Brazilian welcome.
4. Invest in sport
That would be the advice from Locog chairman Lord Coe. It explains Team GB's 65 medals, 29 of them gold. He sets out a recipe of four ingredients - world-class governing bodies for the sports, world class coaching, nurtured talent and high and predictable levels of funding. Some argue that's a luxury for any country. That's what works, he counters.
5. Bring everyone on the journey
Approval ratings showed a mixed picture of how excited other parts of the UK were in the run-up to London's Games. In a relatively small nation, it was still hard to bring all four corners of the country on board.
Hosting Olympic football in Cardiff, Glasgow, Coventry, Newcastle and Manchester, as well as Wembley, helped.
Brazil is a humongous country with very different socio-economic standards across the picture and has its work cut out.
It also plans the multi-city football approach. It may need more than that.
6. Find your spirit and put it out there
Surely this should be no problem for Brazil, the home of carnival, samba, world-class sport, "Alegria" - its spirit. For Britain it was the sense of humour. From the quirky nature and self-deprecation of the opening ceremony, through the light touch of the volunteers, to Mo Farah refashioning Usain Bolt's lightning pose into a Mo-bot. Rio needs to find its identity and bottle it for the world.
7. Present a modern face
London's opening ceremony had the Queen and Isambard Kingdom Brunel. But the monarch was cast in a light we haven't seen her in before - "arriving" out of a helicopter, playing along with 007 James Bond. And ceremony director Danny Boyle looked to the present and the future, from Sir Tim Berners-Lee to texting.
The venues' architecture has been described as modern, beautiful, challenging, a mixture of permanent and recyclable venues. The logo and lettering of London 2012 was modernist. The Games aimed to inspire the next generation.
Brazilian journalists say Rio 2016 "can't be all samba and sequins". But the Olympics cost: if Brazil is to capitalise on that investment, it needs to show its modern self off to the world.
8. Front-load your medals
A top tip from IOC president Jacques Rogge himself, this one. He advised London to stage events in which Team GB were likely to win medals early on in the schedule, to boost the national mood and pull the country into the Games. Once Lizzie Armitstead won Britain's first medal on day two, the mood was "fantastic" and you couldn't keep pace for all the metalware, says Rogge. He passes the same advice on to Rio.
9. Sort out transport and security
A housekeeping point, perhaps, but a major one. These were the two major worries in the run-up to London 2012. In the end, the transport was fine, save a few minor Tube delays. The security threat level was set at substantial, but all the planning put in place was to a severe rating from the Home Office. Rio's mountainous geography and Brazil's more emerging economy, and comparatively high murder rate and drugs trade, present their own challenges.
10. Make a lot of items in blue, yellow and green
The colours of the national flag were everywhere among paying fans at London 2012. It was partly due to the Jubilympics. It is a summer like no other for Britain with the Queen's Diamond Jubilee, the torch relay, the Olympics and the Paralympics yet to come.
There is money to be made in everything from hats to shoes and the outfits and inflatable hands in between. The red white and blue brought colour to the Games here and may have boosted the economy in hard times.