The C1Pager control's tabs follow a zero-based index, meaning that the index of the first tab is zero. By default, the PageIndex property will be set to zero ("0"), and the first page will have focus at run time. To change which page is selected at run time, set the PageIndex property to a different number in the index. For example, if you have four pages and want the last one to be selected at run time, you would set the PageIndex property to 3.