Before The Race Begins

Before the race begins, the horses are ridden in front of the stand. They must be at the starting post at the correct time.
Blinding hoods or any type of shutter hood are forbidden.
No preliminary jumps are allowed before a steeplechase or hurdle race.
The start is usually from starting stalls, but sometimes from a starting gate or by flag with the horses started in a straight line as far as possible.
In flat races the horses are drawn for starting positions, with number 1 on the inside.
An unruly horse may be withdrawn by the starter.
No horse, when stalls are used, may start from outside the stalls or be held inside the stalls.
After The Gun...

A horse is considered to have started once it has come under starter's orders.
A false start may be declared and the race restarted if there is a fault in the starting mechanism.
In steeplechase or hurdle races, if the horses fail to return after the recall signal, the race is void. If only one horse returns, it is awarded a walkover.