I've tried a variety of planners and planner software throughout my career.  Though I make good use of the electronic planning programs I still like the old fashioned paper and pencil format best.  The Action Day Planner is lightweight, easy to carry to and from meetings, and offers lots of space for making notes and reminders.  The calendar and To Do list are on the same page which prevents me from forgetting something plus, in a meeting, I don't have to flip pages to access them both.  Makes me look more efficient because I am more efficient!