For any organisation to be successful in working with volunteers, it is important that the planning will to include volunteers is initiated before the recruitment of the volunteer itself is begun. Before including volunteers it is important that you consider: why you want to include volunteers and what you want the volunteer to help your organisation achieve. Having a brainstorm about the subject before could be useful including both volunteer co-ordinators and the member of staff which would be working with the volunteer or managing the volunteer.

Alternative organisation can experience that they wish to design a role specific for a volunteer, it could be if a candidate with some very specific skills offer to volunteer in the organisation. Organisation could try to prepare for situations like this by having an updated list ready with specific task it would like to have someone taking care of, which would make the reactive creation of role description easier.
 

Source: Volunteer England