There are five licenses available in Gran Turismo 4. Acquisition of each license is progressively more difficult to achieve than the last. Each license enables the player to enter more difficult events in career mode. Driving Missions become available when the International B license is passed, with later missions unlocked at International A level.
The Licenses are (in increasing level of difficulty):
Each license consists of sixteen driving tests and one optional Coffee Break. Performance for each test is graded to one of four levels: gold, silver, bronze or fail. All 16 tests must be completed to at least a bronze level to acquire the license and a prize car; subsequent prize cars are awarded when all tests are passed to silver and gold levels.
Licenses can be skipped by pressing the following button combos once 365 in-game days have been passed and while on the license test screen:
- Passing any license test (bare minimum): Select, R1, Select, R1, Select, L2, L2, R2, R2, L1, Select, L1, Select
- Getting gold on any individual license test: Select, Select, R1, R2, L2, L2, Select, L1, R1, Select, R2, L1, Select
In the PAL and NTSC-J versions, if the player also has a Gran Turismo 4 Prologue save, they can transfer their GT4 Prologue license progress to GT4. Green level licenses grant the B License while red level licenses grant the A License.