To send to part of a group, click on the “Groups” tab. You will be presented with a list of your groups. Click the arrow to the right of the group that you want to send to to, show the list of contacts in that group. If you have previously selected contacts in another group you will need to click “Ok” to the message that appears. By default, all of the contacts will be selected. You can go through the list and remove the contacts that you do not want to send to by clicking the check box to the left of the number. You can use the dropdown to order by Firstname, Lastname, Custom1, Custom2, Custom3 to make filtering easier. Any contacts that are checked when you send will be sent to.