ONE Space Only
After Resume Sentences, Please!
The use of two spaces is an old-fashioned practice that is still rather common today, particularly among those over 40.
Unfortunately for job seekers, certain stylistic choices can make recruiters and executives assume that you’re too old and out of touch to be relevant. Of course, some of those recruiters and executives use two spaces, themselves! But the practice is on its way out.
I recommend everyone use only one space on a resume to conserve space, to appear modern and up-to-date, and because I think it looks cleaner.
Further Reading
Space Invaders: Why you should never, ever use two spaces after a period.
Slate.com
Nothing Says Over 40 Like Two Spaces After a Period!
CultofPedagogy.com
Double Spacing After a Period Could Reveal Your Age
LifeHacker.com
Two Spaces After a Period
Grammar Girl – QuickAndDirtyTips.com