IDEA and its supporting documents emphasize the importance of parents participating in the process, but the majority of the team is school personnel, who are paid to be there. Schools often handle the bulk of IEP organization, writing the IEP, scheduling the meeting and so on.
IDEA does not define how long an IEP meeting should be, so parents should ask for clarification if they are unable to locate it.
The IEP is supposed to be developed by the IEP team at the IEP meeting, but this does not necessarily mean predetermination. The key is that the team members are not steadfast in their decisions and are open to changing them.
The length of an IEP meeting should be as long as it needs to be, as schools are under pressure to do more with fewer resources. However, for some parents, there is not enough time to discuss all that they wish to discuss.