When we work with a charity, the partnership has a time-frame and we call the duration of a particular partnership, a fund-raising campaign. Thus, each charity has its own campaign.
A standard campaign lasts for two months. However, it can be prolonged or renewed at a later date, if the charity so wishes.
As far as possible, we try to time the fund-raising campaigns we run for the charities in such a way that they coincide with the charity's own projects (a fund-raising event, the launch of a new activity, an advertising campaign, ...) which the charity would like us to support and publicize.