Perform-Safe includes measures and equipment which help prevent hazards from occurring, warning against them at an early stage, or assisting in critical situations.

Perform-Safe features fitted to the GL-Class include:

- HOLD function and Hill-start assist to prevent rolling back.
- ESP Trailer Stability Assist
- Tyre pressure loss warning system, or optional tyre pressure monitoring system
- Adaptive brake lights - which start flashing to warn the traffic behind when the driver is braking in an emergency
- High quality, individually adjustable seats
- Interior climate control
- User friendly information systems, with multi-function steering wheel and multifunctional displays
- Optional extras available for the GL-Class include Bi-Xenon headlamps with Active Light System (standard on GL 500) for substantially improved illumination of the road when driving straight ahead or cornering.