Toyota's European Retailer Meeting IV picked up gold in the Business Event of the Year category at the Visit London Awards.
The event was run by Maritz, which received the accolade last week.
Toyota Motor Europe's conference for two groups of 3,000 delegates was held at Excel London on 28 May - 1 June and was designed to update dealers on the company's mid- and long-term business objectives and the latest product developments.
Toyota Marketing's director, Paul Van der Burgh said: "Having received feedback from many retailers and attendees, it's clear that we really inspired and motivated our guests. It was a world-class experience."
Maritz managing director Nick Bender said the agency was "thrilled to bits" to win the award.
"We run many events world-wide, but London always has a special place in our hearts," he said. "Toyota's ERM was on an impressive scale that enabled us to showcase the best of London's amazing landmarks and develop our relationship further with Excel London."
Agency Jack Morton worked on production for the conference.
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