[dba-SQLServer] outer joins?

Hello:

Can I ask for the group's opinion about something?  Is there any performance 
differences between an INNER JOIN and an OUTER JOIN query?  I know the two 
joins may or may not produce the same resultset (depending on data) but I am 
curious if anyone has come across any difference in terms of performance, 
generally speaking of course.  Should OUTER JOINs be avoided in general 
unless absolutely necessary?

Thanks

Billy