Rail operators Southern and Gatwick Express have joined the Govia Thameslink Franchise (GTR).
Three Passenger Services Directors (PSD) for Southern Mainline and Coast, Southern Metro and Gatwick Express services have been appointed.
A spokesman for Southern said the move would not change ticket validity for passengers.
GTR’s Thameslink Programme will introduce three new train fleets, 10,000 additional peak-time seats into London, a £50m investment in station improvements and a ‘transformation’ in train travel when it completes in 2018.
Gatwick Airport train station is due to get a £120m upgrade by 2020.
Angie Doll, head of Service Quality for GTR, has been made PSD for Gatwick Express.
She said: “My overall priority is to improve passengers’ experience of travelling on Gatwick Express from start to finish, so we’re working much more closely with Gatwick Airport to make sure our services are integrated.
“We’ll be upgrading the website and app to make ticket buying easier. There will be a fast and reliable service on new trains, with on-board staff to give our passengers help and information.
“We’re also planning a new station for 2020 with improved layout and passenger information.”
A spokesman for Gatwick said: “Gatwick Airport train station is getting a major upgrade with a £120 million redesign transforming the stations and passenger experience. Work will start in 2017 and be completed in 2020 delivering a doubling in size of the station concourse area, more lifts and escalators to improve access to all platforms and intuitive passenger flow.
“This major station upgrade will be delivered alongside a significant increase in capacity on rail services through Gatwick, between Brighton and London and services to Cambridge and Peterborough by 2018.”
Southern’s former deputy managing director, David Scorey is PSD for Southern Mainline and Coast.
He said: “One of my key priorities is to improve the reliability of our services. With the new timetable in place our passengers should already have noticed a change for the better, and we will work hard to continue this progress.
“I want to build strong relationships with our passengers, listening to them and making sure our services match their needs.
“And we’ll give them accurate, up-to-date journey information from start to finish.”
Southern’s ex-commercial director, Alex Foulds is PSD for Southern Metro. He said: “The Southern Metro carries a large proportion of GTR’s customers, generally over relatively short journeys, so I want to ensure that passengers have a reliable turn-up-and-go service supported by excellent information.
“Many passengers already use ticketing smartcards and I aim to build on this, as it’s not just more convenient, but also helps us understand passengers’ travel needs.
“I’ll also make sure that they have clean and well-maintained stations and trains, with good facilities and shops.”