The Commonwealth prosecution process involves a number of different steps and a range of different people. The following flowchart provides an overview of the typical steps in the prosecution process:  

https://www.cdpp.gov.au/sites/g/files/net2061/f/Criminal-Prosecution-Process-Chart_0.pdf  

(NB: I found a link on our website to 2 documents. One is quite wordy but this one is a good flow chart which simplifies the process).

How long this process can take really depends on the individual case. In most cases, the prosecution process will take a matter of months. However, in other cases, it can be long and complicated. This can often be the case where the offences being prosecuted are complex and/or where trials and appeals take place.

If you wish to discuss how long the particular case you are involved in is likely to take, please contact the relevant CDPP case officer.