You can create a group calendar in Outlook, but it's limited to 4-5 people, there is no security, no availability sorting, no roles, no reporting and no scalability. If this is okay, read on, otherwise take a look at the Outlook Scheduling tool from Timewatch is this lifts these limitations in Outlook. To create an Outlook Team calendar, have each member of the team add the calendars for the other members of the team to their calendar. Next, have everyone delegate access rights to everyone else in the group. Now everyone can see everyone else and edit their appointments.