The brightest WTA stars, including Germany's Angelique Kerber, were on hand at the opening ceremony.
Andrea Petkovic, the No.1 player from the home country, was also in attendance on Monday night.
Caroline Wozniacki, a former Porsche Tennis Grand Prix finalist, met the press on the red carpet.
Maria Sharapova, the three-time defending champion in Stuttgart, also shone on the red carpet.
Ana Ivanovic and Sabine Lisicki joined Kerber, Wozniacki and Sharapova for a group shot on the way in.
The players walked onto center court with kids from their respective fan clubs at the tournament.
Some spoke to the crowd as well - Petkovic is always a popular figure at her home tournament.
Carla Suárez Navarro, Agnieszka Radwanska and Ekaterina Makarova were also among those in attendance.
As were Petra Kvitova and Simona Halep - two of the biggest favorites for the title this week.
Sharapova has never lost a match at the Porsche Tennis Grand Prix, going 13-0 lifetime here.
This is the only WTA event she's ever won three times - she's looking to up that to four this week.
Ivanovic and Wozniacki are both former No.1s, and both Dubai Duty Free Global Brand Ambassadors.
The Porsche Tennis Grand Prix switched from indoor hardcourts to indoor clay beginning in 2009.
Lisicki is Germany's only Grand Slam finalist of the new millennium - Wimbledon two years ago.
The night didn't stop there. WTA Rising Star Garbiñe Muguruza was among the guests at the dinner.