Employers generally like to get annual leave off their books.  

Forced Leave:  Employers can force staff to take leave during an annual closedown (see the modern award), or if they have 8 weeks accrued and you give written notice of at least 8 weeks of when they must start the leave.

Cashed Out Leave:  For some employees, you can cash out their annual leave.  The cashing out for enterprise agreement and award free staff has just been extended to Award employees.  The cash out deal must be written, must be voluntary, at least 4 weeks annual leave must be left once the cash out is paid and must meet the following tests:

For more information contact Peter McNamara and have a look at Sections 92, 93 and 94 of the of the Fair Work Act 2009.