Can I included appointments from my "other" calendars for indentifying
busy/free times?

For example, if someone wants to book/schedule an appointment can I set
outlook up so that my personal/other calendar appointments are included to
show my busy/free time. If I have a personal appointment that makes me not
available that is not on my default calendar I want to show that I'm not
available based on the date/time of the appointment on my personal calendar...