To further complicate the issue, I work in a different location to Plazbot, and have never heard of the system he described.
Ours is done in six month blocks, 14 months in advance. Every six months you will put in for the leave you want between 14 and 20 months from now. The group has maximum number of people who can be on leave at once. If more than that number want leave at the same time the leave rostering person will go back and look ate what each person had last year, and give priority to those who didn't have leave that time last year. In practice, outside school holidays and Christmas there aren't often issues.
One problem though is when you join a group and get rated, the leave roster has already been decided for the next year and a half, so your options will be limited.
Last edited by Nautilus Blue; 16th Sep 2012 at 12:37.