It may seem quaint now, but it was common in the 40s and 50s for companies to require their women employees to resign when they marry.
The memo above, dated January 10, 1951, put a "temporary modification" on IBM's personnel policy that effectively allowed its female employees to remain working after marriage and allowed the company to hire married women in the first place. It was sent in by Marc Sobel The Society Pages' Sociological Images: Link - via The Atlantic